COVID-19 in Alberta
COVID-19 data included in the interactive data application are up-to-date as of end of day August 08, 2022, unless stated otherwise.
total deaths ⚱
newly reported cases, yesterday
percent positivity, 7-day average
average age at death ⚱
CharacteristicsTable 1. COVID-19 cases in Alberta by age group and gender
- A large body of evidence suggests that vaccines are safe and effective against COVID-19.
- All viruses evolve over time through genetic variations. These changes can cause the emergence of new “variants” of the original virus and may have different properties than the original virus, such as increased transmissibility or the ability to cause more severe disease. Omicron, along with its sub-variants, is the currently circulating variant of concern (VOC) in Alberta.
- Omicron has demonstrated increased transmissibility and capacity to evade the body’s immune response compared to previous versions of the virus. This occurs whether this immunity was generated by infection, vaccines, or both. Evidence suggests that a previous infection with COVID-19 or vaccination against COVID-19 are both less effective in preventing Omicron infection than previous variants.
- Vaccine effectiveness (VE) is a measure of the protection a vaccine provides for the population. It compares the risk in the vaccinated compared to the unvaccinated.
- Vaccines may also become less effective over time in preventing people from becoming infected with COVID-19 due to waning immunity, with the Omicron variant decreasing the effects even further. However, COVID-19 vaccines continue to strongly protect people against being hospitalised and from dying with minimal waning at 7-8 months after the last dose.
- For people with two doses of a COVID-19 vaccine, a booster dose is recommended at 5 months after the second dose, and at least 3 months following infection with COVID-19, to increase the level of protection against severe outcomes.
- After a third dose of an mRNA vaccine, protection against symptomatic COVID-19 infection increases and then appears to wane over time.
- Protection against severe disease continues to give good protection even months after immunization. Two doses of a vaccine are effective, but a third dose will offer better protection. After a third dose of an mRNA vaccine, protection against severe outcomes like hospitalization is boosted.
- Fourth doses, or second boosters, are most important for those at high risk of severe outcomes. For considerations on these doses, see https://www.alberta.ca/article-choosing-a-second-vaccine-booster.aspx
A systematic review of the evidence published between December 2021 and April 2022 in The Lancet Infectious Diseases found that the VE of a primary series (for most people, this is two doses) against infection by Omicron was lower that for previous variants and waned over time with nearly all protection lost by 4-6 months post second dose. VE against severe outcomes was maintained and remained more stable. The figure on page 20 of this document helps to illustrate the results from the evidence, for both the primary series as well as for a booster dose.
Boosting increased the VE against infection with Omicron (about 60%) and against severe outcomes (90%). Although protection against infection waned significantly over 4-6 months, this review showed that VE against severe disease remained high at over 80%. [1, 2]
An evidence review published by McMaster University on June 22, 2022, also examined the effectiveness of COVID-19 vaccines against the Omicron variant. It found that in general, people with a primary series continue to have a good level of protection against hospitalisation and death due to COVID-19 for 7 to 8 months after being vaccinated. A booster dose increases this protection against COVID-19 related hospitalisations, although there is some decrease after several months. 
Note that this data is current up to July 19, 2022 and will be updated periodically as new information emerges.
Higdon, MM, et al. 2022. Duration of effectiveness of vaccination against COVID-19 caused by the omicron variant. The Lancet Infectious Diseases. Published online June 22, 2022. Accessed at: https://doi.org/10.1016/S1473-3099(22)00409-1
Higdon MM, Baidya A, Walter KK, et al. Supplement to: Duration of effectiveness of vaccination against COVID-19 caused by the omicron variant. The Lancet Infectious Diseases. Published online June 22. Accessed at https://www.thelancet.com/cms/10.1016/S1473-3099(22)00409-1/attachment/3ba9ad38-48b8-46a3-a993-baddc6bf8bbd/mmc1.pdf.
Bacon, SL, et al. 2022. COVID-19 living evidence synthesis #10 (version 10.7): What is the long-term effectiveness of available COVID-19 vaccines for adults, including for variants of concern and over time frames beyond 112 days in those with a primary series and beyond 84 days in those with a primary series and an additional dose? The Montreal Behavioural Medicine Centre, META group. Published online June 22, 2022. Accessed at: https://www.mcmasterforum.org/docs/default-source/product-documents/living-evidence-syntheses/covid-19-living-evidence-synthesis-10.7---what-is-the-long-term-effectiveness-of-available-covid-19-vaccines-for-adults.pdf?sfvrsn=4c92f905_5
- National Advisory Committee on Immunization (NACI)
- McMaster Forum COVD-19 Evidence Network to support Decision Making
- United States Center of Disease Control (CDC)
OutbreaksTable 2. Summary of open COVID-19 outbreaks in Alberta.
|Facility Type||Total Number of Outbreaks|
|Supportive Living/Home Living Sites||40|
|Acute Care Facility||31|
|Long Term Care Facility||24|
Severe OutcomesTable 3. Total Hospitalizations, ICU admissions and deaths (ever) among COVID-19 cases in Alberta by age group