Updated: Feb 3
A newer variant of SARS-CoV-2 designated as B.1.1.529 was reported to the World Health Organization or WHO on 24th November 2021. This newer variant was first of all detected in collected specimens on 11th November, 2021 in Botswana and 14th November, 2021 in South Africa.
On 26th November 2021, WHO designated it as B.1.1.529 (Omicron) and classified it as a “Variant of Concern”. On 30th November 2021, the United States (US) also designated “Omicron” as a “Variant of Concern” and on 1st December 2021, the first confirmation of Omicron in the United States was identified.
Center for Disease Control (CDC) has collaborated globally with public health as well as Industrial partners towards learning in terms of Omicron along with continued monitoring of the course of the disease. The CDC has made use of genomic surveillance throughout the course or duration of this pandemic for tracking various variants of SARS-CoV-2, a virus that is responsible for causing COVID-19. It acts by constantly informing public health care practices. However, there is not much clarity regarding its speed, extensiveness of severances of disease it may cause, and the efficiency of currently available vaccines and medicines against this newly discovered variant.
What are the previously known COVID-19 variants?
Throughout the ongoing COVID-19 pandemic disease, numerous COVID-19 variants have been shown to emerge. SARS-CoV-2 has continued to undergo mutation along with evolution. At the same time, due to genetic mutations in its “delta” variant, its transmissibility or speed of spread may be more rapid or transmissible. Thus, making it more contagious when compared to the original type of “SARS-CoV-2” that was discovered in December 2019.
The “SIG Variant” classification system has defined four categories of variants of SARS-CoV-2:
(a) Variants Being Monitored or VBM: These include Alpha (B.1.1.7 and Q lineages), Beta (B.1.351 and its descendent lineages), Gamma (P.1 and its subsequent lineages), Epsilon variant that includes B.1.427 and B.1.429 strain, Eta strain (B.1.525), Iota or B.1.526 variant, Kappa or B.1.617.1 strain, 1.617.3 strain, Mu (B.1.621 and B.1.621.1) strain and Zeta (P.2) variant.
(b) Variant of Interest or VOI
(c) Variant of Concern or VOC
(d) Delta (B.1.617.2 and AY variants)
(e) the newly discovered, Omicron (B.1.1.529 variant) and
(f) Variant of High Consequence or VOHC: Till now, no variants have been discovered under this category.
Newer SARS-CoV-2 variants are constantly seen to emerge. Hence, a better system of surveillance may be able to identify more such strains or variants. Most of the newer variants have been demonstrated to fade away. These include a few of the earlier variants that were considered as Variants of interest or VOI. It has been hypothesized that if B.1.1.529 variant has enough transmissibility for outcompeting pre-existing Delta variant, there is a possibility that it may disappear similarly.
How is Omicron different from other COVID19 variants?
The B.1.1.529 has been discovered as having a total of 32 genetic mutations in its genetic structure that is responsible for the “Corona-virus spike protein" when compared with the original SARS-CoV-2 strain that was first of all identified in Wuhan city located in China. Most of these genomic mutations are present in numerous other Variants of Concerns that include the Delta variant, however, most of the other strains may not exhibit.
It has been postulated that by looking at the large numbers of genetic mutations that have accumulated in a single episode of burst, this variant has been thought to have undergone evolution during chronic infectivity of an immune-compromised subject, most probably within an untreated HIV or AIDS patient.
A few of the genetic mutations that are found in various other Variants of Concern may include an “N501Y” mutation that helps in improvement in spike protein binding with other cellular receptors along with a “D614G mutation” that has been considered to increase replication of the virus. Both of these mutations are capable of making this virus greatly contagious. Others mutations include K417N and T478K types of mutations in its genetic structure. These mutations might help this virus to avoid host neutralizing antibodies that are generated either through vaccination or a previous COVID-19 infection.
What are the earlier symptoms of COVID19 and how is Omicron different now?
There is no information to suggest that Omicron causes different COVID-19 symptoms from other COVID-19 variants. It is not currently known if the Omicron variant is more or less severe than other strains of COVID-19, including Delta. Studies are ongoing and this information will be updated as it becomes available.
It is important to remember that all the variants of COVID-19 can cause severe disease or death, including the Delta variant that is dominant worldwide, that is why preventing the spread of this virus and reducing your risk of exposure to the virus is so important.
However, a larger amount of data is required for knowing if the newly emerged infections due to “Omicron” and of which, especially, any re-infections and/or break-through infections among the people who had been fully vaccinated may result in greater severity of illness and/or death when compared with the infections due to other SARS-CoV-2 variants.
How can Omicron transmission be stopped or slowed down?
The Center for Disease Control or CDC has issued recommendations regarding wearing a mouth mask in all public in-door settings with areas of considerable or higher transmission at the community level irrespective of one’s status of vaccination. In addition, the CDC gives advisories regarding the use of masks and information concerning the use of a proper type of mask that is completely dependent on one’s circumstances.
Whenever any virus undergoes wide circulation and causes a variety of infections, there are increased chances of mutation of that particular virus. Thus, there is a greater chance of spreading the viral infection due to higher opportunities for viruses to undergo genetic mutations.
Newer variants of SARS-CoV-2 such as the Omicron continuously remind us that this pandemic is still ravaging the population. Hence, all individuals must get vaccinated along with the continuation of preventive measures against the spreading of this virus that include maintaining physical distancing, wearing masks, regularly washing hands, and maintaining proper ventilation of indoor and closed areas.
There are various “Self-tests” that may be done within homes and are easy to perform thus producing quick results. If one’s self-test has given a "positive result”, it is better to stay home or undergo isolation for ten days, wear a mask if one has any contact with other people, and also, call one’s health-care provider. If a person has any queries regarding the result of the "self-test”, one must call their healthcare provider or the concerned department of public health. Till there is complete knowledge concerning the risk of Omicron, it is important for one to continuously make use of protective measures.
Currently, all vaccines are capable of protecting against the severe type of illness, any hospitalization, and death. Although, the occurrence of breakthrough infections in people who have been completely vaccinated may occur. Hence, continued use of protective measures is still required.