Omicron

 Rise of the Omicron Virus

    

    As the number of vaccinated individuals continue to increase each day, the long-lasting COVID-19 pandemic comes closer to nearing an end. However, things seemed to take an unexpected turn when the World Health Organization designated the new SARS-CoV-2 variant, B.1.1.529, or Omicron, as a variant of concern for its large number of mutations which can lead to increased infection and escape from immunity. The first known confirmed Omicron sample was collected in South Africa on November 9 2021. There have been many other coronavirus mutations but what worries researchers most is Omicron’s rapid rise in South Africa, which suggests the variant could result in an explosive increase in COVID-19 cases worldwide. On December 1, 2021, there have been 8,561 recorded Omicron cases in South Africa. As of December 4, the Omicron variant has spread to over 40 countries and territories, including the United States where it was first detected in California. So, what makes Omicron a variant of concern? Will the current vaccines be effective against Omicron? Will Omicron lead to new round of lock down?

Omicron Mutations

    The Omicron variant has a total of 60 mutations compared to the original Wuhan variant. Of these mutations, 32 affect the spike protein and many of these mutations are located in a region that recognizes receptors on human cells. The large number of mutations may reduce immunity in people who were previously infected and in vaccinated individuals. Anthony Fauci of the National Institute of Allergy and Infectious Diseases says that "the mutations seen in Omicron and in other variants suggest that they are associated with increased infectivity." Other than a speculated increased infection rate, very little is known about the effects of these mutations. Scientists are in the process of measuring the ability of neutralizing antibodies triggered by previous infections and vaccinations to stop Omicron from infecting cells.    

Vaccinations and Infection Severity

There have been reports of breakthrough infections involving the Omicron variant in COVID-19 vaccinated individuals (including the first Omicron case in the U.S.) So, are current vaccines less effective in preventing infection by the Omicron variant than other variants? Scientists say it's not yet clear how effective the vaccines will be against the omicron. Immunity studies suggest that modest levels of neutralizing antibodies may protect people from severe forms of COVID-19. Paul Bieniasz, a virologist at Rockefeller University in New York City, advocates for a booster shot in light of the new Omicron virus saying that "third doses supercharge neutralizing-antibody levels, and it’s likely that this will provide a bulwark against Omicron’s ability to evade these antibodies. Other aspects of the immune system, particularly T cells, may be less affected by Omicron’s mutations than antibody responses.

Although it's still too early to come to a conclusion about the severity of COVID-19 disease caused by the Omicron variant, Fauci, in reference to data from South Africa, stated that "it appears with the cases that are seen, we are not seeing a very severe profile of the disease." However, severity, hospitalization, and death are lagging indicators so it will take at least several more weeks before any definitive conclusions can be made about the severity of the variant.

Conclusion

     The variant's large number of mutations are concerning to scientists and preliminary evidence suggests an increased risk of reinfection with Omicron but a possibly less severe disease profile. In spite of all the recent data, Omicron is still a very new and under researched topic. As time goes on and more data becomes available, more reliable information can be determined on the variant. For now, it's important that people continue following safety precautions especially with this new and relatively unknown variant circulating the globe. Finally, with data suggesting that the Omicron variant has increased infectivity, it's more important than ever to get vaccinated and also consider a booster shot.

Sources

1. Callaway, Ewen, and Heidi Ledford. “How Bad Is Omicron? What Scientists Know so Far.” Nature News, Nature Publishing Group, 2 Dec. 2021, https://www.nature.com/articles/d41586-021-03614-z.

2. “Classification of Omicron (B.1.1.529): SARS-COV-2 Variant of Concern.” World Health Organization, World Health Organization, https://www.who.int/news/item/26-11-2021-classification-of-omicron-(b.1.1.529)-sars-cov-2-variant-of-concern.

3. Upright, Ed, and Melissa Macaya. “December 7, 2021 Omicron Variant Latest Global News Updates.” CNN, Cable News Network, 8 Dec. 2021, https://www.cnn.com/world/live-news/omicron-coronavirus-variant-12-07-21-intl/index.html.