Open this photo in gallery A health care worker speaks to a test patient as they prepare for the opening of the COVID-19 Assessment Centre at Brewer Park Arena, in Ottawa, on March 13, 2020. Justin Tang/The Canadian Press

Health officials in at least two provinces are limiting testing for COVID-19 to prioritize the sickest patients or those who have not travelled outside of Canada but show symptoms, in order to curb potential supply shortages.

The changes in Ontario and British Columbia are meant to conserve supplies and ensure the health system has the capacity to continue testing as the number of cases escalates, potentially at a rapid pace. Health officials say that for most people, the recommendation to self-isolate after travelling, even if they show mild symptoms, should be enough.

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Public Health Ontario says there’s an increased global demand for viral nasal swabs due to COVID-19, and “in an effort to ensure swabs are available where most needed,” the volume will be limited.

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Health Minister Christine Elliott’s office said people who haven’t left the country and experience symptoms will take priority in testing for the time being.

“In an effort to maintain capacity and make better use of supply, and in recognition that anyone travelling outside of the country is being asked to self-isolate for 14 days, we’re prioritizing those individuals without travel history with symptoms,” said Travis Kann, Ms. Elliott’s director of communications.

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“We expect to return to expanded testing as soon as we’re confident in stable supply. To do so, we’re actively working with our manufacturing and supply chain partners to procure additional test kits."

Public Health Ontario said it is also looking into other swab types to increase testing.

“Please be assured we are working diligently to address this issue. Please monitor your inventory closely and reorder only as required,” said a notice on the website.

B.C.'s provincial health officer, Dr. Bonnie Henry, said the province is limiting its testing on people connected to active clusters of local COVID-19 transmission, health care workers and residents in long-term care facilities.

Dr. Henry said people who have returned from travel, even if they have symptoms, don't need to be tested if they follow advice to self-isolate and don’t require additional care. She added that it no longer makes sense to narrow in on a handful of countries as the pandemic spreads around the world

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“People with mild symptoms and returning travellers who are isolating at home do not need to be tested unless you get sick enough to require health care,” she said Saturday.

"We need to focus on clusters and cases where there has been transmission so we can stop those transmission chains.”

Health officials in Alberta are also taking steps to discourage people who don’t need to be tested from clogging up testing sites or its 811 health line.

Alberta created an online self-assessment tool to provide advice about whether someone needs to be tested. The tool recommends people with symptoms who have travelled or been in contact with someone else with a confirmed case of COVID-19 call its 811 health line to determine if they need testing. For almost all other cases, aside from people experiencing severe symptoms such as difficulty breathing, the tool says no testing is required.

The province has also added resources to its 811 system, which has become overwhelmed during the outbreak.

The province’s chief medical officer, Dr. Deena Hinshaw, says only people with active symptoms will be tested.

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“If someone is completely well and they have no symptoms, they do not need to be tested,” said Dr. Hinshaw. “Testing is only for people who are sick.”

Open this photo in gallery Travellers pass a YYZ airport code sign in the international arrivals lounge at Pearson airport, in Toronto, on March 13, 2020. CHRIS HELGREN/Reuters

The Alberta government also published a list of flights that could have exposed passengers to COVID-19, including which seats on those flights are most at risk. At-risk passengers should self-isolate and monitor for symptoms, said Dr. Hinshaw; other passengers should monitor for symptoms but do not need to self-isolate.

Most people diagnosed with COVID-19 experience mild or moderate symptoms, such as fever, cough and shortness of breath, and the vast majority of those who contract the virus recover. The Public Health Agency of Canada says the risk to the general population is low.

However, for some, including Canadians aged 65 and over, those with compromised immune systems and those with pre-existing conditions, the illness can be much more severe. Among the Canadians diagnosed with the illness so far, fewer than 15 per cent have required hospitalization.

Ontario reported 24 new cases of the disease on Saturday, for a total of 103 in the province, with five cases resolved. Few details were immediately available, but at least six of the new cases were linked to recent travel outside of Canada.

B.C. added nine new cases on Saturday. The provincial total is 73, including one death. Six patients have recovered.​

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The province recently put out a call for retired doctors to return to work if the pandemic worsens. The registrar of the College of Physicians and Surgeons of British Columbia says other provinces are doing the same.

Saskatchewan announced four more presumptive cases; the provincial total is currently at six.

Alberta reported 10 new cases, bringing the provincial total to 39. Two of the new cases, patients in their 60s, are in intensive care.

Prince Edward Island and Newfoundland and Labrador both reported their first cases.

Meanwhile, the federal government urged Canadians abroad to return home while they still have a chance as countries around the world impose ever-tighter travel restrictions in a bid to curb the spread of COVID-19.

With a report from the Canadian Press

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1 to 9 10 to 99 101 to 1000 Over 1000 cases Que. Ont. Alta. B.C. Sask. Man. Nunavut N.W.T. Yukon N.B. N.S. P.E.I. Nfld.

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