U of T Modelling Shows Ontario Must Keep Distancing to Continue Opening Up
University of Toronto researchers have found fresh evidence that Ontario’s physical distancing measures have worked. But their newest models suggest that without more testing and tracing, an increase to more than 50 percent of pre-COVID physical contact would quickly overwhelm the province’s ICUs.
The model is a worst-case scenario that shows how quickly Ontario would lose ground if people stop distancing as the province continues to open services and businesses.
“The point of this research is to show how effective physical distancing is but also how tenuous its effect it is,” says Asst. Prof. Ashleigh Tuite, lead author of the study, which was published May 27 online in the Annals of Internal Medicine. “Will people continue to practice hand hygiene, distancing and masking?”
In the model, 50 percent means returning to half the typical interactions a person might have on a typical, pre-COVID day. This scenario assumes Ontario will continue to test and trace cases at the current level, even as more of the province opens up.
The authors hope that will not stay the case.
“This really is a call for ramping up testing and contact tracing,” says Tuite. “If we had that in place, we could think about relaxing distancing more. This would allow us to find local hotspots more quickly and break ongoing chains of transmission.”
Tuite says she was encouraged by the recent outcry over crowding in Trinity Bellwoods Park on a sunny Saturday because it shows Torontonians are still strongly committed to distancing.
The results are similar to previous models developed by the researchers, including DLSPH Profs. David Fisman and Amy Greer. But it’s updated with the latest evidence on the percentage of patients who are asymptomatic, the length of time people are infected before symptoms occur, and the percentage of people getting tested and traced.