This week, the World Health Organization (WHO) classified the Omicron variant of the SARS-CoV-2 virus as a Variant of Concern (VOC). With the Delta variant already spreading worldwide, this news reinforced the need for quick and accurate data collection about these mutations.
However, as more variants emerge that task becomes increasingly complex – presenting new challenges to public health researchers. Our latest insight brief, What’s in a variant? The complexity of generating and using accurate COVID-19 data, explores what makes variant information particularly difficult to document and use. We’re highlighting some key terms and facts below.
So, what is a variant?
Variants of a virus are mutations in its structure that occur when cells replicate. These different versions of the virus are often benign, but sometimes they acquire traits that make the original strain more harmful.
The role of genomic sequencing
Genomic sequencing – a process that identifies mutations that change a virus’ structure and function – is an invaluable tool that helps researchers track and learn about variants of the SARS-CoV-2 virus.
Impact of viral changes
Variants can have different characteristics than the original SARS-CoV-2 virus. For example, new strains may be more transmissible or more severe – differences that could pose a greater threat to the public. This information then helps inform major mitigation strategies, such as mask mandates.
Variant of Concern (VoC)
There are many different terminologies used to describe COVID-19 variants – ranging from broad to specific. At the broadest level, the most threatening variant strains of the SARS-CoV-2 virus are classified into two categories: variant of interest (VOI) and variant of concern (VOC). VOIs have genetic markers predicted to increase transmissibility and virulence, or the potential to evade immunity. VOIs are escalated to VOCs when there is documented evidence of these changes in the population. The Omicron variant – which possesses these genetic markers – has been classified as a VOC.
Looking more information on variants? Check out our four-part blog series that inspired the insight brief: