Omicron coronavirus variant: All your questions answered

COVID-19 variant Omicron is spreading fast around the world. More countries are announcing the arrival of the new variant every day. Travel restrictions around the globe threaten to return to the level of last year when the pandemic was at its peak. Doctors say the new variant (named after the Greek alphabet omicron) transmits faster than the Delta variant of coronavirus.

The variant was first reported in South Africa. It is considered more infectious than other variants so far reported because it has undergone multiple mutations. Mutation is the process by which changes occur in a living organism’s genetic material which can alter its behavior like infection rate and immunity against medical treatment.

What is Omicron?

Omicron is the new variant of coronavirus SARS-CoV-2 that is causing COVID-19 pandemic. WHO has formally named it B.1.1.529.

Where did Omicron variant originate?

The Omicron variant was first detected in South Africa on November 24, 2021, and is continuing to spread to other countries. WHO has designated it as “a variant of concern.”

Is Omicron different from the Delta variant?

The Delta variant declared a Variant of Interest (VoI) on May 11, 2021, after the strain appeared in India first. Omicron has undergone more mutations than the Delta variant and dozens of the mutations have occurred on the spike protein that the Covid-19 vaccines target.

Why is the Omicron strain a variant of concern?

Genomic studies show that the Omicron strain has a high number of mutations. The high rate of transmissibility of the strain is because these mutations are in the spike protein of the virus. Experts say 32 of these mutations affect the spike protein that helps the invading virus attach itself to human cells. The spike protein produces the antigen, which is the main target of antibodies that are generated by the human body’s immune system. Most widely administered vaccines also target the spike protein preventing infection. It is feared that the change in the structure of the spike protein may make it difficult for most vaccines to neutralize the virus by preventing the infection.

Which countries have reported Omicron infection?

While local transmission of the virus has been confirmed in South Africa and Botswana, the virus has been detected in several southern African nations. Outside Africa, the variant has been detected in travelers reaching Australia, Austria, Belgium, Britain, Canada, Czech Republic, Denmark, Germany, Israel, Italy, the Netherlands, Portugal, Spain, Sweden, and Hong Kong.

Has the new variant affected international travel?

Many nations including the United States and the United Kingdom have banned flights from southern African countries including South Africa, Botswana, Lesotho, Eswatini, Namibia, Botswana, Zimbabwe, Mozambique, Malawi, Zambia and Angola. European Union is considering an identical ban as many nations are already witnessing a surge in the Delta variant.

How does WHO name SARS-CoV-2 virus variants?

WHO’s expert committee has been naming the coronavirus that causes COVID-19 after the Greek alphabet. The first variant to be identified was named, understandably, as Alpha and the next three as Beta, Gamma and Delta respectively. A new variant is first categorized as Variant under Monitoring (VUM). If it is found to be infectious it is named Variant of Interest (VoI). If the variant turns out to be highly transmissible, it is categorized as Variant of Concern (VoC).

Omicron variant was designated a VuM on November 24, 2021, and the threat perception was upgraded to VoC on November 16, 2021. On the other hand, the Delta variant was designated as VoI on April 4, 2021, and re-categorized as VoC on May 11, 2021.

Currently designated Variants of Concern (VOCs)⁺:

WHO label	Pango   lineage•	Additional amino acid changes monitored°	Earliest documented   samples	Date of designation
Alpha	B.1.1.7	+S:484K +S:452R	United Kingdom,   Sep-2020	18-Dec-2020
Beta	B.1.351	+S:L18F	South Africa,   May-2020	18-Dec-2020
Gamma	P.1	+S:681H	Brazil,   Nov-2020	11-Jan-2021
Delta	B.1.617.2	+S:417N +S:484K	India,   Oct-2020	VOI: 4-Apr-2021  VOC: 11-May-2021
Omicron*	B.1.1.529	-	Multiple countries, Nov-2021	VUM: 24-Nov-2021 VOC: 26-Nov-2021

 

Are there any more Variant of Interest (VoI) on the WHO list?

There are two strains that have been identified as Variants of Interest (VoI). They have been named Lamda, designated on June 14, 2021, and Mu, designated on August 30.

Currently designated Variants of Interest (VOIs):

WHO label	Pango   lineage*	Earliest documented   samples	Date of designation
Lambda	C.37	Peru, Dec-2020	14-Jun-2021
Mu	B.1.621	Colombia, Jan-2021	30-Aug-2021

 

Will governments shut down businesses again like last year?

It is too early to say something about the course the Omicron variant will take given the nature of the genetic mutations that have occurred. However, a silver lining is that national governments have learned how to handle a pandemic from last two deadly waves of the coronavirus. Moreover, the higher awareness of communities about the pandemic and preventive measures could help tone down its pace of progress. Although the currently available vaccines are yet to be tested for efficacy against the new variant, some may weaken the virus. Overall, the human race is better positioned to handle Omicron than the previous variants.

Cover picture credit: Mullen J, Tsueng G, et int., and tCfVSB.