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What do we know about the Omicron variant?

What do we know about the Omicron variant?

This article was published on
December 7, 2021

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The Omicron variant is a new, likely highly transmissible COVID-19 variant with many mutations. It was first detected in South Africa in November 2021 and later that month was deemed a Variant of Concern by the World Health Organization.

The Omicron variant is a new, likely highly transmissible COVID-19 variant with many mutations. It was first detected in South Africa in November 2021 and later that month was deemed a Variant of Concern by the World Health Organization.

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What our experts say

The Omicron variant is a newer iteration of the COVID-19 virus. It was first identified in South Africa on November 24, 2021 from a sample collected on November 9, 2021.

The variant is said to have been circulating in Europe during a similar time frame, with the first detection there occurring on November 19.

We do not know where the variant first emerged, but we do know it is now spreading in dozens of countries. The disease monitoring and surveillance system in South Africa is where it was first detected, but not necessarily where it originated.

On November 26, 2021, the World Health Organization (WHO) named Omicron a Variant of Concern. The WHO has classifies some variants under this category because of their potential to be more contagious, cause more severe illness, or reduce the effectiveness of some COVID-19 treatments or vaccines.

As of now, Omicron appears to be more transmissible than the original COVID-19 virus but does not appear to produce more severe symptoms. As of this writing, only one report from South Africa has shown that the virus may cause milder symptoms. This has yet to be confirmed through further research and may only reflect the health and ages of the local population, instead of the virus itself.

When Omicron first spread through South Africa, case counts around 200 per day in mid-November recently reached 16,000 per day in early December. Unlike many other nations, the Delta variant's circulation in South Africa is expected to be low in comparison so the Omicron variant might not have had to "compete" with the Delta variant in order to infect more people.

There appears to be community transmission of the Omicron variant throughout Europe and Australia but most cases appear to be asymptomatic or mild, according to the European Center for Disease Prevention and Control.

We still do not know if Omicron can evade vaccine protection but some early data suggests fully vaccinated people might be able to transmit and become infected with COVID-19 due to this variant. We will likely know within a few weeks how effective vaccines are against the variant and what kind of protection a previous infection has on the variant.

We are still learning about the Omicron variant every day, so it is too early to say whether or not it will impact the spread of the virus, vaccine effectiveness, recovery, immunity, or other topics.

As South Africa has seen an exponential rise in cases—particularly in Gauteng province—health officials around the world are awaiting more information about Omicron. When the Delta variant was established as a Variant of Concern it took between four to six weeks before we knew it had greater ability to transmit to others. If South Africa's recent rise in cases is any indication (despite lower vaccination rates than several other nations), this variant might be more contagious than others.

Another early study from South Africa analyzed 2.8 million positive COVID-19 samples and determined that some of these infections were found in people who had been previously infected with the virus. Their statistical analysis showed that in their sample, the Omicron variant is at least three times more likely to cause reinfection than previous variants.

One important aspect of the Omicron variant, which we do know, is that it has at least twice as many mutations as we have seen in other variants, with most of those occurring on the spike protein of the surface of the virus. This is an important note because it might increase the virus' ability to latch onto human cells, replicate, and start an infection.

The Omicron variant also has many new and unique mutations unseen with SARS-CoV-2 before and scientists don't know how this might change the behavior of the virus.

From what our earliest analyses tell us, at this rate, it's likely that the Omicron variant will become the dominant variant in many parts of the world.

Scientists are also unsure if the variant emerged in humans or animals, with several species suggested as potential incubators for Omicron.

It does not appear likely that the Omicron variant will make vaccines totally ineffective. A more plausible scenario is that the variant might cause vaccines to be less effective (if peer-reviewed and confirmed research shows an increase in vaccine evasion) but we will not know how much for a while. It is likely that vaccine booster shots will enhance vaccine protection and offer a stronger immune response to the variant. Since chances of reinfection may be higher with this variant, the Omicron likely escapes vaccine and natural immunity to a degree, but we do not know how much.

The Omicron does appear to be the most heavily mutated version of the virus scientists have detected as of now, though the Delta variant still accounts for more than 99% of virus sequences submitted to the world's largest public database.

The Omicron variant is a newer iteration of the COVID-19 virus. It was first identified in South Africa on November 24, 2021 from a sample collected on November 9, 2021.

The variant is said to have been circulating in Europe during a similar time frame, with the first detection there occurring on November 19.

We do not know where the variant first emerged, but we do know it is now spreading in dozens of countries. The disease monitoring and surveillance system in South Africa is where it was first detected, but not necessarily where it originated.

On November 26, 2021, the World Health Organization (WHO) named Omicron a Variant of Concern. The WHO has classifies some variants under this category because of their potential to be more contagious, cause more severe illness, or reduce the effectiveness of some COVID-19 treatments or vaccines.

As of now, Omicron appears to be more transmissible than the original COVID-19 virus but does not appear to produce more severe symptoms. As of this writing, only one report from South Africa has shown that the virus may cause milder symptoms. This has yet to be confirmed through further research and may only reflect the health and ages of the local population, instead of the virus itself.

When Omicron first spread through South Africa, case counts around 200 per day in mid-November recently reached 16,000 per day in early December. Unlike many other nations, the Delta variant's circulation in South Africa is expected to be low in comparison so the Omicron variant might not have had to "compete" with the Delta variant in order to infect more people.

There appears to be community transmission of the Omicron variant throughout Europe and Australia but most cases appear to be asymptomatic or mild, according to the European Center for Disease Prevention and Control.

We still do not know if Omicron can evade vaccine protection but some early data suggests fully vaccinated people might be able to transmit and become infected with COVID-19 due to this variant. We will likely know within a few weeks how effective vaccines are against the variant and what kind of protection a previous infection has on the variant.

We are still learning about the Omicron variant every day, so it is too early to say whether or not it will impact the spread of the virus, vaccine effectiveness, recovery, immunity, or other topics.

As South Africa has seen an exponential rise in cases—particularly in Gauteng province—health officials around the world are awaiting more information about Omicron. When the Delta variant was established as a Variant of Concern it took between four to six weeks before we knew it had greater ability to transmit to others. If South Africa's recent rise in cases is any indication (despite lower vaccination rates than several other nations), this variant might be more contagious than others.

Another early study from South Africa analyzed 2.8 million positive COVID-19 samples and determined that some of these infections were found in people who had been previously infected with the virus. Their statistical analysis showed that in their sample, the Omicron variant is at least three times more likely to cause reinfection than previous variants.

One important aspect of the Omicron variant, which we do know, is that it has at least twice as many mutations as we have seen in other variants, with most of those occurring on the spike protein of the surface of the virus. This is an important note because it might increase the virus' ability to latch onto human cells, replicate, and start an infection.

The Omicron variant also has many new and unique mutations unseen with SARS-CoV-2 before and scientists don't know how this might change the behavior of the virus.

From what our earliest analyses tell us, at this rate, it's likely that the Omicron variant will become the dominant variant in many parts of the world.

Scientists are also unsure if the variant emerged in humans or animals, with several species suggested as potential incubators for Omicron.

It does not appear likely that the Omicron variant will make vaccines totally ineffective. A more plausible scenario is that the variant might cause vaccines to be less effective (if peer-reviewed and confirmed research shows an increase in vaccine evasion) but we will not know how much for a while. It is likely that vaccine booster shots will enhance vaccine protection and offer a stronger immune response to the variant. Since chances of reinfection may be higher with this variant, the Omicron likely escapes vaccine and natural immunity to a degree, but we do not know how much.

The Omicron does appear to be the most heavily mutated version of the virus scientists have detected as of now, though the Delta variant still accounts for more than 99% of virus sequences submitted to the world's largest public database.

Context and background

As we wait for more data to act on the Omicron variant, it is important to remember that the basic prevention methods used against COVID-19 are still the most reliable, including vaccination.

Several vaccine manufacturers are currently performing laboratory tests to potentially adapt their specific vaccines to better protect against the Omicron. This could help slow the spread of the virus and cause fewer infections.

As we wait for more data to act on the Omicron variant, it is important to remember that the basic prevention methods used against COVID-19 are still the most reliable, including vaccination.

Several vaccine manufacturers are currently performing laboratory tests to potentially adapt their specific vaccines to better protect against the Omicron. This could help slow the spread of the virus and cause fewer infections.

Resources

  1. What we know and don't know about the Omicron variant (CNN Health)
  2. Omicron Variant: How worried should we be? A virologist explains (Science Focus)
  3. How the omicron variant unsettled the world in just one week (The Washington Post)
  4. EXPLAINER: What we know and don’t know about omicron variant (AP News)
  5. Classification of Omicron (B.1.1.529): SARS-CoV-2 Variant of Concern (World Health Organization)
  6. CDC Statement on B.1.1.529 (Omicron variant) (United States Centers for Disease Control and Prevention)
  7. Increased risk of SARS-CoV-2 reinfection associated with emergence of the Omicron variant in South Africa (medRxiv)
  8. Omicron coronavirus variant three times more likely to cause reinfection than delta, S. Africa study says (The Washington Post)
  9. Epidemiological update: Omicron variant of concern (VOC) – data as of 3 December 2021 (12.00) (European Centre for Disease Prevention and Control)
  10. Omicron v. delta: Battle of coronavirus mutants is critical (AP News)
  1. What we know and don't know about the Omicron variant (CNN Health)
  2. Omicron Variant: How worried should we be? A virologist explains (Science Focus)
  3. How the omicron variant unsettled the world in just one week (The Washington Post)
  4. EXPLAINER: What we know and don’t know about omicron variant (AP News)
  5. Classification of Omicron (B.1.1.529): SARS-CoV-2 Variant of Concern (World Health Organization)
  6. CDC Statement on B.1.1.529 (Omicron variant) (United States Centers for Disease Control and Prevention)
  7. Increased risk of SARS-CoV-2 reinfection associated with emergence of the Omicron variant in South Africa (medRxiv)
  8. Omicron coronavirus variant three times more likely to cause reinfection than delta, S. Africa study says (The Washington Post)
  9. Epidemiological update: Omicron variant of concern (VOC) – data as of 3 December 2021 (12.00) (European Centre for Disease Prevention and Control)
  10. Omicron v. delta: Battle of coronavirus mutants is critical (AP News)

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