Throughout the pandemic, each province and territory has adapted their testing guidance (molecular and rapid testing) based on several factors, including growing evidence, new technology or devices, laboratory capacity, and epidemiological contexts.6
Further, COVID-19 variants have had significant implications on case and contact management for provinces and territories due to higher transmissibility, potential for immune invasion, and disease severity.6 These implications mean that testing is more conservative since the onset of the pandemic , and as such, the true number of cases and true rate of community transmission is not known.
In general, viruses are constantly changing. Viruses are classified as variants when there have been significant mutations. Variants are of concern when there is an impact to disease spread, disease severity, testing or detection, and vaccine or treatment effectiveness.7
As of December 2021, several COVID-19 variants of concern have been identified in Canada:
- Alpha (B.1.1.7)
- Beta (B.1.351)
- Gamma (P.1)
- Delta (B.1.617)
- Omicron (B.1.1.529)
Considering the Omicron variant, the Public Health Agency of Canada (PHAC) provides the following recommendations for health-care settings:
- Continue to maintain, evaluate, and monitor existing COVID-19 infection prevention and control measures
- Continue to implement and re-evaluate the hierarchy of controls
- When in close contact or within two metres of a person with suspected or confirmed COVID-19, wear a well-fitted respirator, eye protection (e.g., goggles or face shield), gowns, and gloves
- Personal protective equipment for all patient encounters should be based on a point of care risk assessment
Evidence is continuing to evolve on the quantification of aerosol production by aerosol generating medical procedures (AGMP). PHAC continues to recommend the use of fit-tested N95 respirators, eye protection, gowns, and gloves during AGMPs.