EPIDEMIOLOGY, MUTATIONS AND IMPACT OF NEW OMICRON VARIANT (B.1.1.529): A REAL GLOBAL THREAT OF COVID-19 PANDEMIC

The recent emergence of the Omicron variant (B.1.1.529) of SARS‐CoV‐2 has added alarm to the eternal flame of the global COVID‐19 pandemic. Omicron was first identified in Botswana in November 2021. The omicron is thought to be at least three times more infectious than the previous variants. Omicron can cause diseases varying from asymptomatic, mild, and severe infection and people have died from omicron in a second pandemic wave that occurred in March-May 2021. This variant has been detected in more than 77 countries worldwide as per WHO until January 2022. The spike protein is the target of most COVID-19 vaccines and is what the virus uses to unlock access to our body’s immune cells, many of which (69–70del (deletion), T95I, G142D/143–145del, K417N, N679K, T478K, N501Y, N655Y, and P681H) overlap with Alpha, Beta, Gamma, or Delta variants. Some spike protein mutations include A67V, Δ69-70, T95I, G142D/Δ143-145, Δ211/L212I, ins214EPE G339D, S371L, S373P, S375F, etc. Remarkable mutations in the furin cleavage site may increase transmissibility and replication as in Alpha (P681H) and Gamma (H655Y, N679K) and affect the binding affinity of ACE-2 receptor. Though, after many ongoing mutations and adaptation, omicron can efficiently breach the host immunity, leading to prolonged, severe infection, causing more mortality and rapid spread. There is still substantial uncertainty based on ongoing genomic changes, the effectiveness of current and upcoming vaccines, and treatment against omicron. Thus omicron has forced on the world a chance to explore the intricacies of the complex immunological mechanism.