What Are The 12 COVID Variants Identified Till Now? How Are They Classified?

Since the advent of the COVID-19 pandemic, different variants or genetic lineages of SARS-CoV-2 have been emerging all around the globe, with some causing widespread infections, while others are not as severe.

The different variants of COVID-19 are classified as different groups, such as Variants of Interest (VOIs) or Variants of Concern (VOCs) etc., and recently, a new class of SARS-CoV-2 variants designated as Variants Being Monitored (VBM) were added to the list.

Let's take a look at the different types of COVID variants and how they are classified.

COVID-19 Variants: Everything You Need To Know

1. Why do variants develop?

A variant is the result of the changes that occur in viruses. By nature, viruses are always changing, triggering the development of a new strain or a variant of the same virus [1]. In most cases, the variants have the same structure (behaviour) of the virus, but in some, they will have entirely different compositions, which have been observed in the case of the Delta plus variant [2].

Coronaviruses are a large family of viruses and can cause a variety of illnesses, from mild cough to severe respiratory illnesses. The COVID-19 is one such virus that belongs to the family and while it has been reported in animals before, the first human case was the initial report in China [3]. And that is the reason why the virus was named novel coronavirus, as it possessed a structure that was different from the previously reported ones.

2. What are the types of variants?

• Variant of Concern (VOC): A mutation is declared a VOC when a variant for which there is evidence of an increase in transmissibility, more severe disease which requires increased hospitalisation or causes deaths, a significant reduction in neutralisation by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures [4]. Variants of concern might require one or more public health actions, such as notification to WHO, reporting to CDC, local or regional efforts to control spread, increased testing, or research to determine the effectiveness of vaccines and treatments against the variant (Delta plus/AY.4.2). India has classified the new variant of the coronavirus first identified in Europe as a variant of concern, but it's too early to tell whether it poses a significant threat [5].
• Variant of Interest (VOI): Once genetic markers are identified with an association with receptor binding domain or which have an implication on antibodies or neutralising assays, they are termed as Variants of Interest. VOI possess a genetic capability that affects the disease severity, immune escape, transmissibility and diagnostic escape nature of the virus. Currently, there are no SARS-CoV-2 variants that are designated as Variants of Interest [6].
• Variant of High Consequence (VOHC): According to the CDC, a mutation is declared as being VOHC when the prevention measures ad medical countermeasures do not have as much effect as they had with other variants. Currently, there are no SARS-CoV-2 variants that rise to the level of high consequence, cites the CDC [7].
• Variants Being Monitored (VBM): These include variants for which data are indicating a potential impact on approved medical countermeasures that have been associated with more severe disease or increased transmission [8]. VBMs do not pose a significant and imminent risk to public health.

3. What are variants that have been reported?

1. Alpha (B.1.1.7 and Q lineages): Declared a VOC on December 29, 2020, and VBM by September 21, 2021.
2. Beta (B.1.351 and descendent lineages): Declared a VOC by December 29, 2020, and VBM by September 21, 2021.
3. Gamma (P.1): Declared a VOC by December 29, 2020, and VBM by September 21, 2021.
4. Delta (B.1.617.2): First identified in December 2020 and the mutations in Delta plus variant is a VBM now.
5. Epsilon (B.1.427, B.1.429): Declared VOC by March 19, 2021, VOI by February 2021, VBM by 21 September 2021.
6. Zeta (P.2): Declared a VOI on February 26, 2021, and VBM by September 21, 2021.
7. Eta (B.1.525): Declared VOI by February 26, 2021, and VBM by September 21, 2021.
8. Theta (P.3): It is considered a VOI, but not VOC.
9. Iota (B.1.526): Declared a VOI by February 26, 202 and VBM by September 21, 2021.
10. Kappa (B.1.617.1): Declared a VOI by May 7, 2021, and VBM by September 21, 2021.
11. Lambda (C.37): Declared a VOI in Dec 2020.
12. Mu (B.1.621, B.1.621.1): Declared a VBM by September 21, 2021.

On A Final Note...

The SARS-CoV-2 (virus) will keep changing, causing more mutations and more variants. Experts state that it is impossible to predict how those virus changes might affect the population.