WHO classifies India’s ‘double mutant’ Covid a ‘variant of concern’ as its origin country buckles under the world’s worst coronavirus outbreak
- WHO said Monday that the variant that emerged in India is ‘of concern’
- The variant, B.1.617 has three sublineages and is often called the ‘double mutant’ because it has two mutations that help it infect human cells
- It also may be able to evade vaccine protection better than some older strains
- U.S. CDC considers it a ‘variant of interest’ – a downgraded label – and the variant accounts for between 0.5% and 2% of American cases
The World Health Organization (WHO) said on Monday that the coronavirus variant first identified in India last year was being classified as a variant of global concern, with some preliminary studies showing that it spreads more easily.
The B.1.617 variant is the fourth variant to be designated as being of global concern and requiring heightened tracking and analysis.
The others are those first detected in Britain, South Africa and Brazil.
‘We are classifying this as a variant of concern at a global level,’ Maria Van Kerkhove, WHO technical lead on COVID-19, told a briefing.
‘There is some available information to suggest increased transmissibility.’
It comes as India is pummeled by its deadliest wave of COVID-19, with nearly 4,000 people dying a day, and hundreds of thousands of people testing positive every 24 hours. Both figures are assumed to be undercounts.
The U.S. Centers for Disease Control and Prevention (CDC) dubbed B.1.617 a ‘variant of interest’ – a less urgent designation – last week.
Often called a ‘double mutant,’ the strain has mutations to two parts of its spike protein that help it latch onto human cells, B.16.17 has split into three closely related sublineages that together account for more than 75 percent of cases in India, and a little more than one percent of U.S. cases.
Globally, one of the three sublineages of the variant that merged in India now accounts for an estimated 5% of all cases, according to Outbreak.info data. The entire set of B.1.617 variant sublineages (of which there are three) has been classified a ‘variant of concern’ by the WHO
As of Monday, 75% of sequences tested in India for the presence of the B.1.617 mutations were positive, according to Outbreak.info
Public Health England has divided the Indian variant into three sub-types because they aren’t identical. Type 1 and Type 3 both have a mutation called E484Q but Type 2 is missing this, despite still clearly being a descendant of the original Indian strain. It is not yet clear what separates Type 1 and 3
Indian coronavirus infections and deaths held close to record daily highs on Monday, increasing calls for the government of Prime Minister Narendra Modi to lock down the world’s second-most populous country.
The WHO has said the predominant lineage of B.1.617 was first identified in India in December, although an earlier version was spotted in October 2020.
The variant has already spread to other countries, and many nations have moved to cut or restrict movements from India.
American health officials dubbed B.1.617 a ‘variant of interest’ last week, due to its worrisome mutations.
However, the CDC’s variant tracking site does include data on B.1.617, suggesting it accounts for just a fraction of a percent of all U.S. cases.
But according to Outbreak.info, which track the result of global genetic sequencing – a test performed to see what mutations a viral sample contains – suggest that about two percent of U.S. samples tested Monday were positive for B.1.617.2’s mutations.
Sublineage B.1.617.2 is the most common of B.1.617’s deviations. It’s still rare in the U.S, but rising. As of Monday, about 2% of samples tested were positive for its mutations
B.1.617.2 is one of three sublineages of the variant, and seems to be the most common one, though it is not clear if or why some of the variant’s derivations might be more infectious or vaccine-resistant than others.
Van Kerkhove said more information about the variant and its three sub-lineages would be made available on Tuesday.
‘Even though there is increased transmissibility demonstrated by some preliminary studies, we need much more information about this virus variant and this lineage and all of the sub-lineages,’ she said.
Soumya Swaminathan, WHO chief scientist, said studies were under way in India to examine the variant’s transmissibility, the severity of disease it causes and the response of antibodies in people who have been vaccinated.
‘What we know now is that the vaccines work, the diagnostics work, the same treatments that are used for the regular virus works, so there is really no need to change any of those,’ Swaminathan said.
WHO director-general Tedros Adhanom Ghebreyesus said that the WHO Foundation was launching a ‘Together for India’ appeal to raise funds to purchase oxygen, medicines and protective equipment for health workers.
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