Variants of the Virus that Causes COVID-19
Genetic variations of viruses such as the one that causes COVID-19 are not uncommon and many other variants of the SARS-CoV-2 virus have been previously observed around the world this year. Both new variants include mutations (i.e., changes to the genetic material in the virus) on the “spike” protein, which may result in the virus becoming more infectious and spreading more easily between people. These variants have been termed variants of concern (VOCs) and have been associated with evidence of increased transmissibility, severity, and/or possible immune evasion with potential implications for reinfection and vaccine effectiveness.
Multiple variants of the virus that causes COVID-19 are circulating globally. To date, three SARS-CoV-2 variants of public health importance have been identified:
- The United Kingdom (UK) identified a variant called B.1.1.7 (501Y.V1, VOC 202012/01) with a large number of mutations in the fall of 2020. This variant spreads more easily and quickly than other variants.
- In South Africa, another variant called B.1.351 emerged independently of B.1.1.7. Originally detected in early October 2020, B.1.351(501Y.V2) shares some mutations with B.1.1.7.
- In Brazil, a variant called P.1 (previously P.1.1.28) emerged that was first identified in travelers from Brazil, who were tested during routine screening at an airport in Japan, in early January. This variant contains a set of additional mutations that may affect its ability to be recognized by antibodies.
These VOCs harbour many mutations, including some in the receptor-binding domain (RBD) of the spike (S) protein, encoded by the S gene. Mutations in SARS-CoV-2 arise naturally through viral replication. The RBD mutations of interest in the S gene include the following amino acid substitutions: N501Y, K417N/T and E484K. The N501Y mutation is found in all three VOCs. The E484K mutation is found in P.1 and B.1.351. In addition, P.1 carries a K417T mutation, while B.1.351 has a K417N mutation.
COVID-19 Variants of Concern -Guidelines, Policies and Standards
Canadian and International guidelines, policies and standards with regards to COVID-19 Variants of Concern that Infection Prevention and Control professionals may use to support their own documentation and best practices during the COVID-19 Pandemic.
- Statement on the variants of COVID-19 virus found in the United Kingdom and South Africa (PHAC)
- Statement from the Chief Public Health Officer of Canada on February 25, 2021 (PHAC)
- PIDAC Interim Guidance for Infection Prevention and Control of SARS-CoV-2 Variants of Concern for Health Care Settings (PIDAC)
- COVID-19 Variant of Concern: Case, Contact and Outbreak Management Interim Guidance (Ministry of Health)
- COVID-19 P.1 Variant of Concern– What We Know So Far (PIDAC)
- Evidence on Public Health Measures Required for Rapid Control of Variants of Concern (PIDAC)
- Lockdown Duration and Re-opening including Considerations for COVID-19 Variants of Concern (PIDAC)
- SARS-CoV-2 Variants of Concern: Results of Point Prevalence Study (PIDAC)
- Using COVID-19 Data to Inform Reopening Decision-making in the Context of Variants of Concern (PIDAC)
- COVID-19 UK Variant VOC-202012/01 – What We Know So Far (PIDAC)
- COVID-19 Variants (BCCDC)
- Variants COVID-19 (AHS)
- SARS-CoV-2 Variants (WHO)
- New Variants of the Virus that Causes COVID-19 (CDC)