Whenever the assessment centre at Toronto’s Michael Garron Hospital confirms a new case of COVID-19, Jeff Powis and his colleagues pop the patient’s address into Google Maps and look for patterns.
In the middle of May, something jumped out at Dr. Powis, the hospital’s medical director of infection control. Nine newly positive patients lived in the same high-rise building in Crescent Town, an impoverished pocket of residential towers on the city’s east side.
Worried that more transmission was happening below the radar, the hospital and its local partners in Crescent Town set up a mobile clinic, tested 410 people in eight days and found seven cases of COVID-19 that might otherwise have gone undetected.
“Our motivation was to get in there and go hunt it down,” Dr. Powis said, “rather than waiting for it to come to us.”
Taking testing directly to the communities likeliest to be hit with coronavirus outbreaks is the next phase in the battle against COVID-19, especially in the Greater Toronto Area, where daily case counts have stubbornly refused to drop.
Michael Garron Hospital (MGH) has already decided to keep the Crescent Town testing clinic going for a second week and is opening another site in Thorncliffe Park, while the Scarborough Health Network began opening five pop-up test sites this week.
Critics of Ontario’s response to the pandemic say this kind of targeted community testing should have started earlier as it became clear that, outside of seniors’ homes, the virus was gaining a foothold in vulnerable neighbourhoods.
In Toronto, the local public-health unit began publishing mapped data last week that revealed “sporadic” cases of COVID-19 – those unconnected to an institutional outbreak – were concentrated in places that look a lot like Crescent Town.
They are places where many of the residents are poor, racialized, recent immigrants who often perform essential work that puts them in the path of the virus. Some share small apartments with more than one family, making it practically impossible for the infected to separate themselves from the well.
The pattern holds true provincewide: In the most ethnoculturally diverse neighbourhoods in Ontario, rates of COVID-19 are, when adjusted for age, three times higher than in the least diverse areas, according to a Public Health Ontario report that looked at data up to May 14.
Rates of coronavirus-related hospital and intensive-care-unit admissions were four times higher in Ontario’s most diverse neighbourhoods and deaths were twice as high, the report found.
Yet widespread testing of people living in these hot spots was not really an option until the fourth week of May, when the Ontario government broadened its criteria to allow for testing of high-risk members of the public without COVID-19 symptoms.
“You couldn’t really go after the general public and test within the context of communities," said Tia Pham, lead physician at the South East Toronto Family Health Team and one of the co-ordinators of MGH’s assessment centre in Crescent Town.
Now, she predicted, hot-spot testing will allow the system to identify, “little wildfires smouldering," that could be put out on the spot with contact tracing and isolation.
As the testing criteria opened up, MGH and its local partners, including WoodGreen Community Services, worked swiftly to get a mobile testing site up and running in Crescent Town by May 25.
The city of Toronto officially calls the neighbourhood Taylor-Massey, but most of the amenities in the area still carry the Crescent Town name, including a medical practice owned by Alnoor Aziz, the doctor who loaned his space for the pop-up clinic.
Sandwiched between Dawes and Victoria Park roads on the old city of Toronto’s boundary with Scarborough, Crescent Town is made up of six high-rise buildings that are connected by pedestrian walkways located above ground level, making foot traffic invisible to people driving by.
Many Crescent Town residents are newcomers from Bangladesh, including Mohammad Hasan Murad, a 40-year-old father of two who visited the mobile testing site on a sunny afternoon last week.
Mr. Murad, a computer-engineering student who immigrated to Canada in 2016, lives in the building where the first nine cases were identified. He had been feeling weak and was afraid he might have caught the coronavirus, despite mostly staying inside.
“I was a little bit concerned,” he said, “So as soon as I saw the sign, I came down here.”
Mohan Doss, the director of newcomer programs and services at WoodGreen, said local community leaders have been working since March to help Crescent Town residents protect themselves from the virus, putting up informative signs in Bengali and Urdu in lobbies and laundry rooms, and giving out masks at the community’s grocery store and pharmacy.
Those efforts, he believes, have helped prevent the virus from swamping the neighbourhood.
Taylor-Massey’s current rate of sporadic COVID-19 cases is about 280 per 100,000, higher than some of the wealthy communities to its south and west, but significantly lower than the hardest-hit pockets of Toronto’s north Etobicoke area, where rates top 700 cases per 100,000.
Still, Dr. Powis expressed frustration that the system had failed to prevent some of the infections that have already taken hold in Crescent Town. “If I could have been there [with testing] a week earlier or five days earlier, even two days earlier," he said, “I might have been able to prevent that secondary transmission.”
Irfan Dhalla, vice-president of physician quality and director of the Care Experience Institute at Unity Health Toronto, praised the community testing strategy, but warned that testing alone would be insufficient to control the virus.
“Testing has to be followed by contact tracing and a whole lot of education and support so people can isolate themselves," Dr. Dhalla said.
Self-isolation would have been difficult for Crescent Town resident Mr. Murad, who shares a one-bedroom apartment with his wife and 7-year-old son and 9-year-old daughter. The children sleep in the living room.
Fortunately, Mr. Murad tested negative.
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