Understanding Omicron - insights from experts.

Facts about Omicron that journalists need to know:

• Name: World Health Organisation (WHO) named the B.1.1.529 Omicron on November 26, 2021. 
• Reported: Omicron was reported to WHO on November 24, 2021.
• Originally identified: It was identified in Southern Africa in late November 2021.
• Omicron is classified as a Variant of Concern (VOC).*

VOC is a variant for which there is evidence of an increase in transmissibility, more severe disease (for example, increased hospitalisations or deaths), a significant reduction in neutralisation by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures. Source: USA CDC

About the Webinar

The expert panel included Professor Oyewale Tomori @WALETOM, Professor of Virology at Redeemer’s University Nigeria, and the chairman of Nigeria's Ministerial Expert Advisory Committee on COVID-19. Professor Oyewale Tomori served as the regional virologist for the World Health Organisation Africa Region before he was appointed as the pioneer Vice-Chancellor of Redeemer's University, Nigeria. 

Peter Van Heusden, @pvanheus is a Bioinformatician at the South African National Bioinformatics Institute. Peter is also a contributor to ADH and will be the host of a series of ADH tutorials airing this year. The pre-recorded tutorials will unpack the significance of testing and sequencing of COVID-19 variants, the evolution of the virus and more. The live online training will also be hosted in February/March 2022 where participants can ask their own questions. If you are interested in attending, sign up for our newsletter and be the first to know more. 

You can watch the ICFJ Webinar: Deciphering Omicron on youtube here.

Insight 1: Why are there new variants?

Viruses change. 

As the SARS-CoV-2 virus circulates within the infected hosts it accrues changes ‘mutations’.’ Most of these mutations will have no impact on the virus’s properties or behaviour.  However, some of the mutations have led to changes resulting in the emergence of variants. 

Insight 2: What are the possible origins of Omicron?

From Nextstrain.org’s phylogenetic tree below you can see that Omicron (Red) is the product of evolution within an infected SARS-CoV-2 context, which has left no obvious traces of intermediate forms since it diverged from the B.1.1 lineage.

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Peter shared three possible explanations for the missing intermediates from Martin et al (2021) which are: 

Hypothesis 1: That COVID-19 sampling in Southern Africa between May and September 2021 might either have been too sparse or biased, such that  low-frequency variants were not detected amongst high numbers of Delta (blue) variant infections during this time period; 

Hypothesis 2: That long-term evolution occurred in one or more chronically infected people, and within these individuals, intermediate forms remained unsampled; 

Hypothesis 3: The reverse zoonosis to a non-human host, which was then followed by an undetected spread in the non-human hosts and a spillover back into humans. 

At present, the scientific community does not have direct evidence to support or reject any of these hypotheses on the origin of Omicron. However, Martin et al note that a precise origin of Omicron may be identified as new data is collected.

Insight 3: Studies about Omicron are underway

A critical takeaway from the webinar regarding Omicron is that information is limited. There are a number of studies underway in the scientific community to answer questions like: 

• How transmissible is Omicron? and
• How effective are vaccines and other COVID-19 treatments against Omicron?

More information on Omicron will become available in the coming days and weeks providing a more accurate and clearer understanding of this new variant. The slide below from WHO shares the current knowledge available on Omicron.

Lastly, a webinar attendee asked when will the pandemic end; the panellists answered succinctly - it ends when we end it. Protective measures against Omicron include social distancing, good hygiene and vaccinations. We each have a role to play in stopping the spread and reducing the possibility of emerging variants.