Ontario's lockdowns are effective in curbing COVID-19 transmission, study finds
Fencing and blockades sit at the gates of High Park in Toronto on Friday, May 1, 2020. THE CANADIAN PRESS/Frank Gunn
TORONTO -- A new study has found that the Ontario government’s lockdowns in the first wave of the COVID-19 pandemic had a “positive effect” in curbing the spread of the disease.
The model-based analysis of those measures was conducted by researchers at York University, led by director of the laboratory for industrial and applied mathematics professor Jianhong Wu.
Wu’s team found that interventions implemented to prevent the spread of COVID-19 not only significantly reduced the number of people residents had social contact with but also influenced who those people chose to see.
One example given is that because more people were staying home in mid-March that effectively disrupted the contacts they otherwise would have had in their workplace and in the community.
Moreover, the study found individual contacts decreased from 12 people a day to just under seven a day following the closure of non-essential workplaces from March 24 to May 16, among a number of other public health measures introduced by the government that were highlighted in the study.
As well, researchers found that household contacts – people that you live with – increased by 51 per cent, from before the lockdown in Ontario until it ended in May.
Researchers developed a novel methodology to crunch the numbers that looked at variables, such as age and setting to better understand how to disease was spreading. That same methodology was then used to measure the effectiveness of the public health restrictions like school closures and the declaration of a state of emergency.
Researchers found that there was a 46 per cent decrease in contact rate after the Ontario government introduced those interventions.
“These assessments are essential to avoid increases in transmission in vulnerable populations and to plan a smart relaxation of measures that will still protect these populations and inform expected outcomes,” Wu said in a news release issued by York University Wednesday morning. “One of these may be a reintroduction of measures, but more targeted and informed by its induced shift of contacts, in the case of a resurgence.”
Overall, Wu’s team found that “timely and stringent non-pharmacological interventions,” are effective in limiting the spread of an outbreak only if they are enforced until transmission has been significantly reduced.
Ontario is currently operating under the province’s colour-coded COVID-19 framework, which places each of the province’s 34 public health units in one of five categories.
Those categories include varying levels of public health measures that range from very lenient to very strict and a region can be moved to a different category based on the documented transmission trends in the area.
However, speaking to CP24 on Wednesday, York University PhD Candidate and contributor to the study, Zack McCarthy, said that only “time will tell” if those new measures are truly effective, citing “COVID fatigue” which he says is an important factor to consider in the second wave.
“It would be too soon to see just yet to see whether these measures will have an effect,” he said.
“But if they do have the same effect that we saw in the past we can expect reductions to appear in the key markers such as the per cent positivity in [COVID-19] tests.”
In an email to CTV News Toronto, a spokesperson for Premier Doug Ford said that the report demonstrates that the actions taken by the Progressive Conservative government have been successful.
“We know these measures have been extremely difficult on Ontarians, and while these weren’t easy decisions to make, this is just another proof point that they are necessary in our fight against COVID-19," the spokesperson said.
To read the full report click here.