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The World Health Organization said on May 10 that the COVID-19 variant first associated with India last year was being classified as a variant of global concern, with some preliminary studies showing that it spreads more easily.


The World Health Organization said on Monday that the coronavirus variant first associated with 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 associated with 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.”

‘Variant of interest’ vs. ‘variant of concern’: What’s the difference?

SARS-CoV-2, the virus that causes COVID-19, has mutated into many new forms since the pandemic began. Some are more transmissible than the original virus, or more likely to reinfect people who recovered from it, but health officials don’t treat all variants as serious threats unless they meet certain criteria.


  • Definition: To the World Health Organization, a variant of interest, or VOI, is simply a form of the virus that’s shown to have different physical properties than classic SARS-CoV-2, or have new genes that could make it so. The shape of viruses, in particular the protein spikes they use to bind to host cells, is important because a variant with different spikes could be better able to infect cells or resist antibodies. But until researchers can prove that a given variant does those things, it remains a VOI. When national health agencies find a new one, they have to share its gene sequence and case details with their local WHO office. The WHO then gives it a Greek letter designation.
  • Examples: Iota is a variant that emerged in New York in the fall of 2020. It showed some resistance to the antibody drugs used to treat severe COVID-19 cases, but WHO guidance says it’s unclear what clinical effect that really has.


  • Definition: VOCs are types of VOI that have been confirmed as more transmissible or more resistant to existing public-health measures. The vaccines we have now, for instance, are still mostly effective against all forms of COVID-19, but non-medical masks and physical distancing can be less effective because, if the virus is more contagious, it would take a smaller amount of virus-carrying water droplets in the air to spread it from person to person.
  • Examples: The WHO’s list of VOCs so far includes the variants first identified in Britain (Alpha), South Africa (Beta), Brazil (Gamma), India (Delta), California (Epsilon) and Peru (Lambda). All have had documented cases in Canada, though Alpha is by far the most common type.

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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 associated with 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.

Dr. 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,” Dr. 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.

As India struggles under a second wave of the novel coronavirus pandemic, auto-rickshaws have become the latest symbols of hope in Delhi, doubling up as ambulances to help its collapsing healthcare system.


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