Comparing the coronavirus curve

We’ve selected 10 countries, including Canada, to examine the growth of COVID-19 cases over time to help explain Canada’s current situation and the effectiveness of our response.

These charts will be updated daily with the latest numbers.

Not every country has reacted to the coronavirus pandemic in the same way. Some countries have been hit harder than others, and there are complex geographic, demographic and political factors at play that may make one country more susceptible to a surge in cases than another.

Some countries, such as South Korea, took immediate action to slow the spread of the coronavirus by isolating COVID-19 cases and restricting travel. Others, such as Italy and Iran, saw their health-care systems quickly overwhelmed, and the number of cases and deaths there rose dramatically before they put effective measures into place.

These charts use a logarithmic scale to make the trajectory of the pandemic in the selected countries more easily comparable.

Remember, the COVID-19 cases appearing today are a snapshot of infections that happened about two weeks ago. So, the impact of ours and others’ actions won’t be apparent immediately.

Flattening the curve

You have probably seen the term “flattening the curve” used a lot lately. Understanding what it means when it comes to slowing the number of COVID-19 cases is key to seeing how effective a country’s response to the outbreak has been.

An epidemic curve, or “epicurve,” is a graph that shows the frequency of new cases over time based on new infections per day. In many cases, an epicurve follows a bell curve, steadily rising to a peak and then declining as the outbreak burns out when the virus runs out of people to infect.

Flattening the curve refers to when methods like large-scale testing, quarantining of infected individuals and social distancing are used to decrease the number of daily new COVID-19 cases. The aim is to reduce overall infections and keep cases at a number the health-care system can manage.

The exponential growth rate shows how the rate of cases would grow over time if no measures to stop the virus’s spread were put in place.

You can get a sense of how effective containment measures have been by comparing the number of confirmed cases in a country with an exponential growth rate.

Daily new coronavirus cases in Canada

Daily new cases data provides an early indication as to whether a country’s epidemic curve is flattening and if containment measures are working. They are also a good gauge of the current impact on the health-care system.

The latest information from the World Health Organization shows that 15 per cent of COVID-19 infections are severe and require oxygen. Another five per cent are critical and require ventilators. Ensuring the health-care system isn’t overwhelmed is key to containing the coronavirus outbreak in Canada.

Daily numbers aren’t always accurate

Many factors can explain why data for confirmed cases of COVID-19 aren’t always accurate.

Not all countries have the capacity or the will to test for cases extensively or conduct effective contact tracing to find cases in the community, and it can be difficult to verify each country’s data.

We can also see surges in the number of cases when there are a high number of tests done in a short timeframe, if there is an outbreak at a given location, or if there is a significant lag between the time in which efforts to flatten the epicurve are put in place and when results are seen.

It’s also important to understand that countries that test a high number of people will ultimately detect more cases than countries that are not doing as much testing.

This interactive reflects the most accurate information available and is intended to provide Canadians with a visual representation of Canada’s current rate of cases amid the ongoing global pandemic.