The World Health Organization has classified a coronavirus variant, first identified in India, as a variant of global concern.
The B.1.617 variant, also called the triple mutant, was first identified in India in December of last year. The variant is considered responsible for driving the deadly second wave in the country. Moreover, it has spread to more than thirty countries across the world, including the UK. Thus, leading the World Health Organization (WHO) to classify it as a ‘variant of concern.’ According to WHO, their decision is based on preliminary studies showcasing increased transmissibility of the variant.
We are classifying this as a variant of concern at a global level. There is some available information to suggest increased transmissibility.
Maria Van Kerkhove, WHO technical lead on COVID-19
India’s second wave, which began in mid-February, has completely overwhelmed the country’s healthcare system. This past week, the total COVID-19 cases in the region crossed 24 million, and the death toll consecutively stayed at or above 4,000 people per day. In recent days, the daily new cases and number of deaths have seen a slight dip; however, experts believe the actual numbers may actually be much higher than those reported.
According to researchers, the triple mutant has three sub lineages: B.1.617.1, B.1.617.2, and B.1.617.3. Studies have identified key mutations in the spike protein of these variants. These mutations, similar to that of previous variant of concerns, makes the virus spread more rapidly and evade antibodies. Although the link between the variant and India’s surge in cases has not yet been established, there is enough evidence linking the two.
What is a Variant of Concern?
The India coronavirus variant, B.1.617, is the fourth variant that WHO has labelled under variant of concerns. Previously the list included: UK, Brazil, and South Africa variant.
As per WHO’s report, a mutation is labelled as a variant of concern when it fulfils either one of these criteria: increased transmissibility, increased virulence, or decreased effectiveness of treatment and vaccines against the mutation.
Even though there is increased transmissibility demonstrated by some preliminary studies, we need much more information about this virus variant in this lineage in all of the sub-lineages, so we need more sequencing, targeted sequencing to be done
Maria Van Kerkhove, WHO technical lead on COVID-19
Despite the increasing cases of the variant, WHO is optimistic that the current vaccines will be effective against the mutant. Further studies are underway to assess the variant’s transmissibility and its response to antibodies generated by vaccines.
Reference:
Cherian, S. et al. Preprint at bioRxiv https://doi.org/10.1101/2021.04.22.440932 (2021).
