The federal government is expected to release its COVID-19 projections this morning, but there are limits to what the data can tell us.
Forecasting the future is never easy. When the forecast involves a pandemic’s effects on the world’s population and its economy, the stakes couldn’t be higher.
That’s why the COVID-19 modelling the federal government is presenting this morning needs to be read with an understanding of what these models can — and can’t — tell us.
CBCNews.ca will have full coverage of the government’s briefing on its modelling at 9 a.m. ET.
The projections that governments across the country are relying on now are imperfect but still important, because they allow those governments to assess their capacity to handle the spread of the virus, explain the reasons behind restrictive preventative measures and prepare for the future.
The number of COVID-19 cases and related deaths around the world continues to grow. In Canada, we’re still talking about relatively low numbers — about 20,000 confirmed cases and 500 deaths — but the experience of other countries shows us that where we are today is not where we will be tomorrow.
The short-term projections recently published by Ontario, Quebec and Alberta offered stark descriptions of what that could mean for Canada. Ontario estimates the number of deaths in the province by the end of this month could be 1,600. Quebec puts their lowball estimate of deaths by that point at just under 1,300 while Alberta estimates between 400 and 3,100 deaths by the end of the summer.
Extrapolating the Ontario, Alberta and Saskatchewan long-term models to the entire country — the three had similar numbers on a per capita basis — suggests that without any restrictive measures in place, the total toll from the coronavirus pandemic in Canada would be about 14 million infections and nearly 300,000 deaths.
That’s about the same as the total number of deaths in Canada every year from all causes.
These are the kinds of numbers that can concentrate the mind. Premiers Jason Kenney of Alberta and Doug Ford of Ontario have used them to justify the measures their governments have put in place — and to alarm people into taking those measures seriously.
But they also come with a lot of important caveats.
There are significant challenges involved in modelling the future that apply to all situations, from weather patterns to elections to pandemics. Models use existing data to make reasonable estimates of what could happen going forward, taking into account the relationship between different factors and how one thing affects another.
In the case of the COVID-19 pandemic, that means tracking the mortality rate of the disease, how quickly it can spread and what impact physical distancing and other measures have had on that spread — among many other factors.
Inconsistent data, uncertain forecasts
There is a limited amount of data with which to work. Models rely on how the virus has spread in this country, how it has spread in other countries and what has happened in past outbreaks of similar diseases.
But the numbers that do exist are inconsistent. The federal government needs to aggregate information from provincial health systems that compile it in different ways. For example: both Ontar