Toronto’s medical officer of health says the city’s coronavirus outbreak has outstripped case and contact management resources and that immediate, population-level interventions are needed to drive down infection rates.
The Globe and Mail reported on Saturday that Toronto Public Health is so far behind in reaching patients with newly confirmed COVID-19 infections that it has suspended contact tracing outside of outbreaks in congregating settings.
“This means that TPH will only call confirmed cases,” read a TPH e-mail sent to the city’s disease detectives on Friday, obtained by The Globe. “We will not call close contacts. Confirmed cases will be asked to notify their high risk/close contacts to self-isolate.”
In an interview on Sunday, Eileen de Villa said while contact tracing is an important tool in outbreak management, it will not solve the challenge of quickly doubling infection rates in the city.
“We have to move beyond case management and contact tracing strategy and deploy public health measures that are at that policy level, at that population level, that can offer and confer that level of protection that we need for the largest number of people in the shortest amount of time," she said.
On Friday, Dr. de Villa requested the province suspend indoor dining at bars and restaurants, as well as indoor group fitness classes, group recreation and team sports. She also advised Torontonians not to leave home except for essential trips. She had not yet receive a response as of Sunday.
A similar TPH memo also sent by Dr. de Villa on Friday provided further details on practices that have been suspended. This includes collecting or referring high-risk close contacts to other public health departments, or following up with contacts from other local public health departments, and reporting on socio-demographic data, occupation and risk settings for community cases.
David Fisman, an epidemiologist and professor at the Dalla Lana School of Public Health at the University of Toronto, said the suspension of contact tracing is the right thing to do given Toronto’s numbers. With an existing backlog of cases, hundreds more being reported daily and lengthy waits for both tests and results, contact tracing becomes ineffective in controlling the disease, he said. Ontario’s provincial lab system has a backlog of nearly 79,000 tests.
“We currently have people waiting several days for tests, and then long (in some cases, a week) turnaround time on tests,” Dr. Fisman wrote in an email. “Those lags make the results meaningless from a contact tracing point of view.”
He echoed Dr. de Villa’s call to suspend indoor dining at restaurants and scale back on indoor gatherings of all kinds.
“We know case numbers are rising and the frequency of cases in older individuals is too,” he wrote. “We know how that’s going to play out in the weeks ahead. We need to get this under control to avoid extreme disruption and tragedy.”
Ashleigh Tuite, an infectious disease epidemiologist at the Dalla Lana School of Public Health at the University of Toronto, said the suspension of information sharing with other public health departments will have implications for potential spread.
“Thinking about going into the Thanksgiving long weekend, as much as we’re hoping people don’t travel and don’t get together, the reality is there’s going to be some of that happening,” she said. “If you lose that sight because you stop contact tracing, I think that has implications that will be felt across the province.”
The suspension of reporting on socio-demographic data, occupation and risk settings for community cases means public health cannot be as tactical in its response by focusing on racialized communities or specific occupations.
“If you just don’t have the bandwidth to do it, it’s what you have to work with," Dr. Tuite said. “But the trade off is that we are going to have to use blunter measures.”
Kevin Smith, president of the University Health Network (UHN) in Toronto, said he sympathized with TPH’s plight, but disagreed with the decision to scale back contact tracing.
“Our worry is that without contact tracing it does increase the risk of people bringing this virus in to long-term care and hospitals,” he said.
Susy Hota, the medical director of infection prevention and control at UHN, added that she was worried about putting the onus to notify family, friends and coworkers on people who have just learned they’re infected, some of whom will be seriously ill.
“The overall risk is that it’s now up to the individuals who are diagnosed with COVID-19 to be telling their close contacts about their diagnosis,” Dr. Hota said. “Some people will not feel comfortable doing so because of fears of repercussions, especially if you’re talking about close contacts in a workplace. You might feel alienated or like you’d be stigmatized.”
Ontario reported 566 new cases on Sunday, with 196 of them in Toronto, 123 in Peel and 81 in Ottawa. The province also reported seven additional deaths, for a total of 2,975. Health Minister Christine Elliot said “a number” of cases and death reported Sunday occurred in the spring or summer but came to light during an ongoing data review in Toronto.
On Sept. 1, Toronto’s seven-day moving average was 40 new cases every day. On Sept. 29, it averaged 236.
“This illustrates the extent of the threat that we face,” Dr. de Villa wrote in her memo. “The viral spread in Toronto demands quick, aggressive action.”
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