Featured Science

All you want to know about OMICRON

Recently, a new variant of COVID-19, the Omicron, has spread to many countries worldwide in the last few days since it was first identified in Africa almost a month back. After nearly two years of its emergence, the SARS-CoV-2 virus, causing the COVID-19 disease, mutated once again, and the new variant has been termed the omicron variant. Referred to as a COVID-19 Variant of Concern (VoC) by World Health Organization (WHO), it has triggered global travel restrictions, a race to accelerate booster vaccination programmes and renewed calls to address vaccine disproportion. The VoC has emerged after initial variants of the virus infected an estimated 26 crore people and 50 lakh casualties globally. Since December 2020, several coronavirus strains have emerged and become dominant in many countries, creating a new endemic-like situation, with alpha, beta, gamma, and delta variants being most prominent until November 2021.

The COVID-19 pandemic has put a strain on all the healthcare systems worldwide and left an atmosphere rife with anger and frustration due to its widespread negative impacts on social, mental, and economic well-being. Unlike prior variants, Omicron has emerged in an era when vaccine immunity is increasing around the globe. However, the amount of changes in omicron variant means that the effectiveness of antibodies produced by COVID-19 vaccines would be reduced. Fears that the variant may undermine the efficacy of COVID-19 vaccines have led the world to announce an acceleration of booster jab roll-outs in the hope that more antibodies will provide better protection. India reported its first case of the Omicron variant of COVID-19 in Andhra Pradesh on 12th December 2021. Since then, around 200 people have been diagnosed with the disease, in a week, containing the variant; however, its spread is more than 2000 per day globally.

According to WHO, there is no concrete evidence that symptoms associated with omicron mutations differ from other mutations. Currently, the available anecdotal data from clinicians at the front lines suggest that patients with Omicron are younger people with a clinical presentation similar to past variants. Although no alarming clinical concerns have been raised thus far, this anecdotal information should be treated with caution given that severe COVID-19 cases typically present several weeks after the initial symptoms associated with mild disease. Omicron strains cause symptoms similar to other COVID-19 strains, like headache, cough, shortness of breath, fever, fatigue, sore throat, muscle or body aches, a loss of taste or smell, a runny nose. However, WHO indicated that omicron mutations might increase mortality rates compared to other COVID-19 mutations.

The following strategy may help prevent the aggressive spread of Omicron and subsequent VoCs: Increase the COVID-19 testing, impose travel bans, avoid crowded places, increase COVID-19 vaccinations, increase medical infrastructure and facilities. Importantly, existing public health prevention measures, popularly termed as COVID Appropriate Behaviours (CABs), like mask-wearing, physical-distancing, avoidance of enclosed spaces, outdoor preference, and hand hygiene, have remained effective against past variants should be just as effective against the omicron variant. Preliminary observations, which need to be interpreted with caution, indicate that Omicron might spread faster and might escape antibodies more readily than previous variants, thereby increasing cases of reinfection and cases of mild breakthrough infections in people who are vaccinated.

In conclusion, along with several other nations, India also needs to take strict action to prevent the spread of the Omicron variant of SARS-CoV-2 by implementing strategies such as ban on international travel, enhanced genomic surveillance, and sequencing to identify the strains. Finally, more studies are needed to understand better its transmissibility, immunity escape potential, clinical presentation and severity of the disease, and the role of other available diagnostic and therapeutic countermeasures. Further studies are needed to examine the potential efficacy of the currently available vaccines. Several previous studies have stated that anticancer or antiviral drugs could be effective for the delta variant or other variants. Still, more studies are required to explore the efficacy of anticancer or antiviral drugs against the omicron variant.

Based on the data from previous VoCs, people who are vaccinated are likely to have a lower risk of severe disease from omicron infection. A combination prevention approach of vaccination and public health measures is expected to remain an effective strategy.