Variants are classified into the following categories:
Variants of Concern
Variant of Concern (VOC): (Working definition)
- Increase in transmissibility or detrimental change in COVID-19 epidemiology; OR
- Increase in virulence or change in clinical disease presentation; OR<br>
- Decrease in effectiveness of public health and social measures or available diagnostics, vaccines, therapeutics. <br>
Variants of Interest (VOI)
A SARS-CoV-2 variant : (Working definition)
- with genetic changes that are predicted or known to affect virus characteristics such as transmissibility, disease severity, immune escape, diagnostic or therapeutic escape; AND
- Identified to cause significant community transmission or multiple COVID-19 clusters, in multiple countries with increasing relative prevalence alongside increasing number of cases over time, or other apparent epidemiological impacts to suggest an emerging risk to global public health.
Variants Under Monitoring (VUM)
A SARS-CoV-2 variant with genetic changes that are suspected to affect virus characteristics with some indication that it may pose a future risk, but evidence of phenotypic or epidemiological impact is currently unclear, requiring enhanced monitoring and repeat assessment pending new evidence.
Source: World Health Organization