Infographics: COVID-19 in Alberta by the numbers
Staff members wave to family and friends who came out to show support of residents and staff in the McKenzie Towne Long Term Care centre, in Calgary, Alta., Thursday, April 2, 2020. THE CANADIAN PRESS/Jeff McIntosh
EDMONTON -- As the number of COVID-19 cases mounts in both Canada and Alberta, we're getting a clearer picture of how the pandemic is spreading and how the situation here compares to other jurisdictions.
While the daily case count announcements from provincial health authorities are the most eye-catching figures, there's other important numbers beyond newly confirmed cases, including hospitalizations and testing data.
- Tracking every case of COVID-19 in Canada
- COVID-19 in Edmonton: Numbers broken down by neighbourhood
- Infographics: COVID-19 cases in Calgary
This page will be updated daily as new information on Alberta, Canada and international cases of COVID-19 is made available.
Starting the week of June 29 and until Nov 8., the province provided daily data updates Monday through Friday and not on weekends and holidays. Daily updates resumed in early November.
Follow the links below or scroll down to see how the COVID-19 situation is changing in Alberta as the pandemic continues.
- How is COVID-19 growing in Alberta?
- Where is COVID-19 hitting Alberta the hardest?
- How many COVID-19 patients are in hospital? How many have died?
- How is Alberta testing for COVID-19?
- How quickly is COVID-19 being spread in Alberta?
- Which age groups have been most susceptible to COVID-19?
- How does Alberta's COVID-19 situation compare with other provinces? Other countries?
HOW IS COVID-19 GROWING IN ALBERTA?
The province's daily case count announcement is among the most prominent COVID-19 statistics.
The number of new cases represents the number of patients who are newly infected with the coronavirus. The number of active cases in the province can go up or down depending on the number of new recoveries on a given day.
In simple terms, 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.
Recoveries are defined by Alberta Health Services 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.
Daily case counts include both lab-confirmed and probable cases. The case count for a given day is regularly revised to more accurately reflect probable cases that were either later confirmed or determined not to be related to COVID-19.
WHERE IS COVID-19 HITTING ALBERTA THE HARDEST?
Since early April, the province has provided a geographic breakdown of cases for its five health zones, community-level subzones and individual cities.
Alberta Health Services divides the province into five health zones: Calgary, Central, Edmonton, North and South.
A map of those zones can be seen here, and it's important to note that the Edmonton and Calgary zones cover an area significantly bigger than the cities they are named after.
Sizable daily jumps in the new number of cases can't necessarily be attributed to the virus growing, as testing volume and reporting time also influence the data.
For more local data, the province's COVID-19 statistics page has an interactive map showing cases by city and community.
HOW MANY COVID-19 PATIENTS ARE IN HOSPITAL? HOW MANY HAVE DIED?
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.
Until November, the number of hospitalizations and ICU admissions have both remained well below maximum capacities.
Health authorities say the province had set aside about 70 ICU beds for COVID-19 patients.
The province has also 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.
Hospitalization data is often retroactively updated by the province as individual hospitals report data at varying times and speeds.
Deaths are reported daily but a given day's count doesn't necessarily mean all of those deaths happened the day before.
Instead, deaths are reported by the date they occurred and can be attributed several days prior to being publicly announced.
HOW IS ALBERTA TESTING FOR COVID-19?
Alberta has been the top province in Canada measured by per capita COVID-19 testing since near the start of the pandemic.
Nearly 1.5 million Albertans have been tested for the coronavirus so far.
Determining test positivity percentage is not as simple as dividing the daily number of positives by the daily number of tests. This is because a test administered will count for statistics of one day, and a positive result would be recorded in the daily statistics between two and seven days later given the processing time to evaluate a test.
It's also important to distinguish between test volume (the number of tests completed) and the number of people tested as patients can be tested more than once. Each person tested is counted only once in the number of people tested statistics.
The province has made 10 notable shifts in policy around who can be tested.
- March 23: The province announced testing was being focused on at-risk populations and health care workers. At the same time, testing returning travellers was deprioritized to only those showing symptoms.
- April 7: Testing is opened to any symptomatic individuals in the Calgary Zone
- April 13: Testing was expanded to any Albertan with symptoms consistent with the coronavirus.
- April 17: The province announced it would start testing all staff and residents of continuing care facilities for COVID-19 regardless of whether or not they show symptoms.
- May 4: The testing criteria was expanded again to include anyone exeperiencing headache, muscle or joint aches, fatigue or severe exhaustion, nausea, vomiting, diarrhea, unexplained loss of appetite, loss of sense of smell or taste, or pink eye.
- May 11: The province opened testing to asymptomatic residents of the Calgary Zone who work outside their home. .
- May 29: The province announces all Albertans, including those who are asymptomatic, were eligible to be tested.
- September 17: Testing prioritized towards at-risk Albertans and those showing symptoms.
- October 13: the province announced it was moving to an appointment-only testing model.
- October 20: the province paused testing for asymptomatic individuals with no known exposure to infected persons.
HOW IS COVID-19 BEING SPREAD IN ALBERTA?
The province divides the ways COVID-19 is being spread into three categories: travel-related cases, spread via a known source, and spread via an unknown source, or community transmission.
Initially, travel-related cases were responsible for many of Alberta's new COVID-19 cases. But since travel restrictions came into effect, the growth in the number of travel-related cases had largely flattened through early April before gradually rising again through the summer.
Close contact with individuals known to be carrying the virus remains the most common way of spreading COVID-19 in Alberta.
Suspected community transmitted cases, where the carrier isn't immediately known, are an important indicator of how the coronavirus is spreading in a community as well as how successful measures like physical distancing have been in limiting transmission.
Identified cases are investigated by AHS and classified into one of the three categories. The classification can change pending further investigation.
WHICH AGE GROUPS HAVE BEEN MOST SUSCEPTIBLE TO COVID-19?
Since the onset of the pandemic, COVID-19 has affected the elderly more than other age groups as seen in high death and active case counts.
But, younger age groups are not immune, with cases among Albertans under the age of 40 rising to form a majority of all active cases in the province for much of the summer.
HOW DOES COVID-19'S GROWTH IN ALBERTA COMPARE TO ELSEWHERE?
Conclusions drawn from comparing provinces are somewhat limited by widely differing testing volumes and practices among provinces, but the raw data does allow from some contrast.
The above graphs rank provinces by the number of tests they administer and how many confirmed cases they have, both adjusted for population.
Tests are also not without their own biases. More tests will produce more positives, and it's easier to test everyone in a less populous province.
Rates adjusted for population provide a snapshot of the COVID-19 situation on any given day, but experts say the growth of the virus, which is unrelated to population size, is also an important indicator of future trends.