New Delhi: Even as India is stepping up defence against Omicron, a concerning new variant of SARS-CoV-2, the World Health Organisation (WHO) warned that the mutant form could reinfect those who have recovered from COVID-19.
A meeting of WHO's Technical Advisory Group on SARS-CoV-2 Virus Evolution (TAG-VE) on Thursday termed the variant B.1.1.529 - named Omicron - 'a virus of concern,' suggesting an increased risk of reinfection with the variant. Though it has been found that the variant could overcome the immunity provided by vaccines, its virulence is not immediately known.
The variant was first reported to WHO from South Africa on Wednesday. The infected sample was collected on November 9.
According to WHO statistics, three COVID-19 waves have swept across South Africa, with the Delta variant, which wreaked havoc in India, accounting for the majority of infection.
Available genome sequencing reports held that Omicron has spurred the spike in COVID-19 over the past few weeks. The variant spreading to Europe and Asia has now become a matter of concern.
Variant of Concern
Omicron has undergone about 50 mutations compared to other variants, including Delta (B.1.617.2). Some of these mutations are of concern. It has been reported that the spike protein (glycoprotein) alone has undergone 32 mutations. The spike proteins play an important role in the virus infecting the host.
The mutations in Omicron's spike proteins would help the virus to spread. The absence of Non-Structural Protein 6 (NSP6), mutations that help the virus to multiply rapidly are also matters of concern.
The COVID-19 symptoms in those affected by Omicron are similar to that of other variants, according to South Africa's National Institute for Communicable Diseases. However, Omicron could reinfect those who had already been infected and the vaccinated population.
Meanwhile, pharmaceutical firms Pfizer and Merck claimed that their recently developed vaccines are effective against Omicron.