Infographics: COVID-19 in Alberta by the numbers
A pedestrian wearing a mask walks through an empty downtown Calgary, Alta., Wednesday, Dec. 9, 2020. THE CANADIAN PRESS/Jeff McIntosh
This page will not be updated from April 17 onwards. Regular updates will resume April 26.
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.
This page will be updated daily as new information on Alberta, Canada and international cases of COVID-19 is made available.
It's important to note the numbers provided each afternoon are a preliminary tally of the day's COVID-19 situation. Virtually all of those numbers are regularly retroactively updated as health authorities confirm updated and new information.
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?
- What are COVID-19 variants and how are they growing in Alberta?
- How many COVID-19 patients are in hospital? How many have died?
- How is Alberta testing for COVID-19?
- How has COVID-19 affected different age groups?
- How does Alberta's COVID-19 situation compare with other provinces? Other countries?
HOW IS COVID-19 GROWING IN ALBERTA?
The province's daily new 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 cases and 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 including "long-haulers" who may deal with multiple syndromes months after diagnosis.
Alberta Health defines a recovery 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.
In late December, Alberta reported its first cases of the more infectious variants of COVID-19.
The reproduction value, or R-Value, measures the expected number of cases directly caused by one case. It informs if cases are increasing or decreasing and relies on a number of models that estimate past and future factors.
cases are currently increasing, decreasing or staying the same.The value can be calculated using one of several different models which estimate a number of past and future factors around the virus and population. The province has provided the statistic on a weekly basis since Dec. 8.
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 areas 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.
WHAT ARE COVID-19 VARIANTS AND HOW ARE THEY GROWING IN ALBERTA?
Variants occur when a virus develops a set of mutations that change its genetic code enough that it reacts differently than the original strain, but also not enough that it becomes its own virus.
Novel coronavirus variants have been have emerged throughout the pandemic. But, a series of variants that developed in late 2020 drew particular concern due to being more transmissible than the initial strain.
There are also questions about the effectiveness of vaccines against variants as well as their potential to re-infect patients who have already had the coronavirus.
- COVID-19 variant tracker: cases by province and territory
- What you need to know about COVID-19 variants in Canada
On April 11, Alberta Health data showed that for the first time, variants made up a majority of the province's active COVID-19 cases.
Comparisons of variant case volumes across provinces are difficult to make due to the different procedures in each jurisdiction.
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.
All confirmed COVID-19 cases have been screened for variants since Feb. 1, 2021. Alberta Health notes the need for a second screening delays the reporting of variant cases by up to two days, though delays in other provinces are often much longer.
"The vast majority of variants of concern are reported immediately, with only a small number needing follow up testing for confirmation," an Alberta Health spokesperson wrote in an email.
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 B.1.525 variant orginally found in Nigeria.
By mid-March 2021, Alberta recorded its first two cases of the P.1 variant first seen in Brazil.
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.
And, by mid-March data reporting included the number of total, active, recovered and fatal variant cases as well as the number of specimens screened.
Variant cases are a subset of the COVID-19 cases reported daily by the province and are included in daily case counts.
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 and the amount of stress it's placing on the province's health care system.
Until November, the number of hospitalizations and ICU admissions had both remained well below maximum capacities, which Alberta Health has said was around 270 ICU beds.
The province has said the system's capacity to handle COVID-19 patients can be adjusted, but at the cost of fewer beds, staff and other resources for other patients and procedures.
Like all Alberta COVID-19 data, hospitalization figures are often retroactively updated by the province for accuracy as individual hospitals report data at varying times and speeds.
See below to compare hospitalization rates by province.
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, or even weeks, prior to being publicly announced.
HOW IS ALBERTA TESTING FOR COVID-19?
Alberta has been among the top provinces in Canada measured by per capita COVID-19 testing volume since the start of the pandemic.
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.
It's also important to distinguish between test volume (the number of tests completed) and the number of people tested as people are often tested more than once. Each person tested is counted only once in the number of people tested statistics.
In 2020, the province made 11 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.
- February 9: Alberta expanded its rapid testing program to include asymptomatic staff at long-term care and designated support facilities.
HOW HAS COVID-19 AFFECTED DIFFERENT AGE GROUPS?