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       Children sanitize their hands at St. Barnabas Catholic School during the COVID-19 pandemic in Scarborough, Ont., on Oct. 27, 2020.

       Nathan Denette/The Canadian Press

       Health officials in provinces across the country are bracing for a surge in demand for laboratory COVID-19 tests as students head back to school with a fourth wave well under way.

       Experts warn that as the virus – along with run-of-the-mill colds – starts circulating in classrooms and hallways among the under-12 population, for whom there are no approved vaccines, COVID-19 cases are going to rise even faster than they are now. So will a flood of anxious parents looking to have children tested.

       Some fear a repeat of last fall’s problems as demand for testing exploded, particularly in Ontario, where the province’s system was overwhelmed with lineups and backlogs. But provincial officials insist this time it will be different.

       Ontario’s COVID-19 back-to-school plan: hoping, praying and replaying

       Alberta’s hands-off approach to COVID-19 restrictions leaves school boards to issue divergent measures

       What’s the difference between a rapid COVID-19 test and a PCR test, and which one is best?

       In Alberta, where local media say people had to wait two hours at a short-staffed Edmonton assessment centre, testing capacity is being ramped up to deal with back-to-school demand.

       In Ontario, schools in Ottawa and Toronto are being given take-home test kits for use by symptomatic students or for when entire classes are dismissed because of a probable or confirmed COVID-19 case. But in some cases the kits, which rely on the same PCR (polymerase chain reaction) tests and must be sent to a lab, will not be distributed for several weeks as public-health officials and hospitals roll them out to schools.

       Niagara Region’s Medical Officer of Health, Mustafa Hirji, says the province’s testing system has already been slowing down. A month ago, he said, people in his region could book same-day tests, allowing public health to quickly trace contacts and isolate positive cases.

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       Dr. Joe Vipond, bottom, an emergency room physician, leads a sustained protest against the Alberta government ending COVID testing, tracing and isolation in Calgary, Alta., on Aug. 12.

       Jeff McIntosh/The Globe and Mail

       Now, even before most classes resumed on Thursday, he said, it has started taking at least a day or two – and in some cases, three or four days – to book a test. His region used to have three assessment centres, now it only has one.

       “I am absolutely concerned about the capacity for testing,” Dr. Hirji said, adding that his public-health unit has been talking to local hospitals about ramping up efforts.

       “Forty per cent of our unvaccinated population are students under the age of 12. Schools are going to be our biggest concentration of unvaccinated people and I am really worried that schools could be the area where we have the most outbreaks.”

       Testing rules also vary among provinces. Alberta, which recorded nearly 5,000 new cases over the long weekend alone, has no requirement for the health care system to inform school divisions of a positive case in a student.

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       Edmonton Public Schools had 52 cases by midday on Wednesday, just three days into the new school year. Trisha Estabrooks, the board’s chair, said families and staff have notified schools of positive cases.

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       Students line up before attending class on the first day of school in Montreal on Aug. 31.

       Graham Hughes/The Canadian Press

       “It’s not an accurate picture, because unlike last year, we are not receiving notification of Alberta Health Services when we have positive cases in our school,” she said. “It’s like we are flying blind.”

       She said that when schools learn of a positive case, they share the information with other families, but educators are not allowed to dismiss classes.

       “Cases are rising in Alberta, in Edmonton. This Delta variant is aggressive. We have 57,000 unvaccinated elementary students. I fully expect our case counts will rise,” Ms. Estabrooks said.

       In British Columbia, health officials say they can do more than 20,000 lab tests a day and that anyone with symptoms, or who is part of an identified cluster or outbreak, can get a test through the public system.

       In Prince Edward Island, Chief Public Health Officer Heather Morrison said in a release last week that the government was adding a number of COVID-19 testing sites as students and staff returned to school buildings.

       “We all want to have as normal a school year as possible for students, families, teachers and education staff,” Dr. Morrison said.

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       Families and youth aged 12 and older line up at a COVID-19 vaccine clinic at Gordon A Brown Middle School in Toronto on May 19.

       Nathan Denette/The Canadian Press

       Meanwhile, Ontario Health, the agency that oversees the province’s health system, said the province’s diagnostic lab network has a capacity of more than 100,000 tests a day, “and there is sufficient capacity to meet testing needs should they increase, while maintaining turnaround times.” That’s much higher than the 40,000 tests a day the province was struggling to complete last September.

       Ontario’s Chief Medical Officer Health, Kieran Moore, said the province’s recently revised list of symptoms that require a COVID-19 test, which eliminates a runny nose as a trigger, will help keep test demand down. (He said just 1 in 100 children with runny noses were found to have COVID-19, making it not worth it to test all of them. However, the province’s advice is still to keep children with a runny nose home from school.)

       Dr. Moore said discussions have taken place over the summer with pharmacies and local doctors’ offices about their potential role in increased testing. He also said that if case counts in the province increase dramatically, more rapid tests – which do not require lab analysis, but are considered less accurate – could also be rolled out.

       “We have certainly looked across Ontario and thought we have enough capacity. But that can be leveraged, if and when necessary,” Dr. Moore said.

       Ken Farion, medical and operations lead for the Ottawa COVID-19 testing task force, said the system is better prepared to handle increases in demand, unlike last fall where lines snaked around testing centres. In his area, a drive-through testing facility is extending its hours in the coming week.

       But he added that much will depend on whether parents keep sick children home and whether masking and hand-hygiene rules are followed.

       “We don’t have a crystal ball though to know what exactly is going to happen,” Dr. Farion said.

       With a report from Andrea Woo in Vancouver

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