EDMONTON -- Data on COVID-19 is largely focused on the international, national or provincial level, but statistics compiled by CTV News illustrate how the coronavirus is affecting Edmonton and its individual communities.

Alberta Health divides Edmonton up into 15 health subzones named for their home communities. 

Since early April, the province has provided daily updates on the number of COVID-19 active cases, recoveries and deaths in each of those subzones as well as totals for the city itself.

From July 3 to Nov. 8, the province provided data only for Monday through Friday except for holidays, before resuming regular updates again. Where available, data from weekends and holidays are included in the visualizations below.

This page is divided up into six sections: overall city data, hospitalizations, testing, age data, subzone (community)-level data, and methodology.

Scroll down or follow the links below to navigate to each section.

CITY OF EDMONTON

The city of Edmonton is distinct from the Edmonton zone, which includes communities far beyond the city itself.

Unless otherwise specifically indicated, numbers on this page are for the city itself and not the zone.

Note, the 15 subzones seen in the map above cover the vast majority, though not all, of the area inside the city's coroporate boundaries.

See the methodology section below for how Alberta Health defines a recovery from COVID-19. Scroll down or follow this link for historical information on each subzone.

HOSPITALIZATIONS AND DEATHS

Hospitalizations have been reported province-wide since the start of the pandemic, and by health zone since early May, but not by individual cities.

Tracking hospitalizations is an important indicator of how severely the pandemic is affecting Albertans as well as how the coronavirus is taxing the province's health care system. 

Cases are assigned a location by a patient's home address, but hospitalizations are based on the location of hospitalization.

Deaths are outlined below by city boundaries, though they are also reported by health zone and subzone. 

Deaths do not necessarily occur the day before they are reported. They are tracked below by day of reporting as the province doesn't report the actual date of death by city.

The province has said the system's capacity to handle COVID-19 patients can be adjusted, but at the cost of fewer beds and other resources for other patients and procedures.

On Dec. 1, Alberta Health Services said approximately 2,250 acute care beds and 425 ICU beds were being allocated for COVID-19 patients. 

TESTING DATA

 

Testing data for specific cities isn't available so the above graph displays data from the Edmonton Zone as opposed to the city itself. 

The Edmonton Zone had a population of just over 1.4 million people in 2018, according to AHS. The same year, the province estimated the city of Edmonton's population at just over 1 million people.

Test positivity percentage provides insight into what proportion of daily tests are returned with positive results. It can generally be calculated by dividing the number of positive results by number of tests, but Alberta Health cautions that confirmed cases can occasionally appear the reporting system two to three days later. The precise figure takes that delay into account and is provided by the province.

SPREAD

 

The reproduction value, or R-Value, measures the expected number of cases directly caused by one case. It informs how rapidly the coronavirus is spreading and has been cited by the premier as key metric in determining government policy around restrictions. 

The value can be calculated using one of several different models which estimate a number of factors around the virus and population.

The province has provided the statistic for the province as a whole as well as for the Edmonton and Calgary zones (not cities) and the rest of Alberta on a weekly basis since Dec. 8.

VARIANTS

Variants of the novel coronavirus have emerged as COVID-19 continues to spread with evidence from abroad showing they are more transmissible and can impact developed antibodies.

By February, variant cases had appeared in all 10 provinces with modelling data from Ontario suggesting a variant could quickly become the dominant strain of the disease.

There are also questions about the effectiveness of vaccines against variants as well as their potential to reinfect patients who have already had the coronavirus.

In Alberta, identifying a variant case requires a separate screening, meaning individuals are notified twice: once for a positive COVID-19 test, and again if a variant is identified. 

These variants are identified by the location of their discovery or through letters and numbers. In an effort to avoid stigmatizing entire cities and countries where these variants first emerged, an effort has been made to rename them.

In late December, Alberta reported two kinds of variants: the B.1.17 variant first identified in the United Kingdom and the B.1.351 variant first reported in South Africa. Other variants reported in Canada, but not in Alberta, include the P.1 variant first identified in Brazil and the B.1.525 variant orginally found in Nigeria. 

 

Alberta began reporting the number and type of variant cases in early January on weekdays. By mid-February that reporting was expanded to seven days a week. 

Cases are reported by total numbers and broken down by health zone, though more deatils like active cases and recoveries are not yet published. 

Variant cases are a subset of the COVID-19 cases reported daily by the province and are included in daily case counts.

AGE DATA

 

Similar to testing data, age-specific data is only available relative to health zones, and not to specific cities. 

The above heat map shows the Edmonton zone's evolving active case count since the start of July, grouped by age ranges. 

COMMUNITIES

The province's interactive data app allows for filtering of data the local level. Below are visualizations showing the how active case counts have changed in Edmonton communities (subzones) over time as well as the same figure but adjusted for the population of each subzone.

Scroll down or follow these links to see how the number of total cases, active cases, recoveries and deaths have changed over time in individual subzones:

Abbottsfield, Bonnie Doon, Castle Downs

Duggan, Eastwood, Jasper Place

Mill Woods South & East, Mill Woods West, Northeast

Northgate, Rutherford, Twin Brooks

West Jasper Place, Woodcroft East, Woodcroft West

Beaumont, Fort Saskatchewan, Leduc & Devon
 
St. Albert, Sherwood Park, Stony Plain & Spruce Grove

 

METHODOLOGY

Boundaries

The graphs above were assembled using two versions of the province's interactive data map, each with different borders. 

The city-specific graphs draws data from the city of Edmonton as defined by its geographic corporate boundaries.

The community-level graphs draw data taken from the province's 15 Edmonton-area health subzones.

Their boundaries closely resemble the city's borders but with some exceptions. As a result, some areas within Edmonton's corporate boundaries, largely near the city's southern boundary, are included in suburban health zones.

Cases are attributed to the subzone of a patient’s primary residence. You can see population estimates for each subzone here.

Case Counts

The updated daily case count reflects the number of new, active cases (people who are now newly ill with COVID-19). 

The daily change in active cases are determined by subtracting the number of newly recovered cases from the number of new cases. A positive value represents an increase in net active cases, with a negative value indicating the opposite.

The province often revises data, and reclassifies cases to other health zones or subzones which can cause a sudden rise or drop in cases for a given location.​ Case counts can rise or fall retroactively as probable cases are taken into account and data is updated for accuracy.

Reclassifications can occur for a number of reasons, including: 

  • A patient's contact information was updated to reflect his or her proper address. 
  • Further testing revealed a patient did not, in fact, contract COVID-19. 
  • Data entry errors.

The province published new numbers daily March, April, May and June, with subzone data being available since early April. Starting the weekend of July 4, the province will release updated data on weekdays only, with no scheduled updates on holidays and weekends.

Recoveries

Recoveries are defined by Alberta Health as follows:

  •  A return to health after 14 days of isolation for those with COVID-19 but who experienced only mild symptoms.
  •  If hospitalized due to COVID-19, anyone who does not require additional hospitalization or treatment in the 10 days after they left the hospital.
  •  If tested, such as a health care worker, two negative tests at least 24 hours apart.

It's also noteworthy that in data parlance, a recovery is someone who contracted COVID-19 but didn't die due to the virus. A recovery is not necessarily synonymous with a return to full health as many patients report severe symptoms long after their infections have cleared.