Covid-19-2: “Not Indian”; variant B.1.617 in 44 countries, says WHO
Virendra Pandit
New Delhi: On a day the Union Ministry of Health and Family Welfare took umbrage at sections of media identifying the coronavirus B.1.617 strain as “Indian”, the World Health Organization (WHO) said the variant has been found in 44 countries so far.
The B.1.617 variant, first identified in India in 2020, has been found in 44 countries, the world health watchdog, which had classified it as a ‘variant of concern’ (VOC) on Monday, said on Tuesday.
The UN body routinely assesses if variants of SARS-CoV-2 result in changes in transmissibility and severity, or if they lead to changes in public health and social measures’ implementation by national health authorities, media reported.
“As of May 11, over 4,500 sequences have been uploaded on the Global Initiative on Sharing All Influenza Data (GISAID) and assigned to B.1.617 from 44 countries in all six WHO regions,” the global health body said in its latest weekly epidemiological update published on Tuesday.
GISAID is a primary source to provide open access to genomic data of the novel coronavirus responsible for the Covid-19 pandemic.
The WHO has also characterized the lineage B.1.617 as a VOC, which meant those considered more dangerous variants than the original form of the virus first seen in China in late 2019.
That danger stems from a variant’s higher transmissibility, lethality, and resistance to vaccines, or either of them.
B.1.617 contains three sub-lineages, which differ by few but potentially relevant mutations in the spike protein – this helps the virus enter the human cells, as well as the prevalence of detection globally.
“At the present time, WHO has designated B.1.617 as a VOC based on early evidence of phenotypic impacts compared to other circulating virus variants,” the world body said.
According to it, B.1.617 sub-lineages appear to have higher rates of transmission, including observed rapid increases in prevalence in multiple countries.
Viruses in the B.1.617 lineage were first reported in India in October 2020.
The resurgence in Covid-19 cases and deaths in India have raised questions on the potential role of B.1.617 and other variants such as B.1.1.7 in circulation.
A mutation means a change in a nucleic acid base or amino acid molecule, and a virus containing this change is termed a mutant. Mutations eventually accumulate to generate variants that differ from the original virus more and more, and so, a variant can have limited or even cumulative mutations.
A recent risk assessment of the situation in India conducted by the WHO found that the resurgence and acceleration of Covid-19 transmission in India had several potential contributing factors.
These include an increase in the proportion of cases of SARS-CoV-2 variants with potentially increased transmissibility, several religious and political mass gathering events which increased social mixing, reduced adherence to public health and social measures.
The exact contributions of each of these factors on increased transmission in India are not well understood, media reports said.
Nearly 0.1 percent of positive samples in India have been sequenced and uploaded to GISAID to identify SARS-CoV-2 variants.
The prevalence of several VOCs, including the B.1.1.7 and B.1.612 sub-lineages, increased concurrently to the surge in Covid-19 cases reported in India, according to the WHO.
“While B.1.1.7 and B.1.612.1 variants have begun to wane in recent weeks, a marked increase in the proportion of viruses sequenced as B.1.612.2 has been observed over the same period,” it said.
“Since the identification of these variants through late April 2021, B.1.617.1 and B.1.617.2 accounted for 21 percent and 7 percent of sequenced samples from India, respectively.”
A preliminary analysis conducted by WHO using sequences submitted to GISAID suggests that B.1.617.1 and B.1.617.2 have a substantially higher growth rate than other circulating variants in India, suggesting potential increased transmissibility.
