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Coronavirus Explained: What Are COVID Variants And Variants Of Concern?

According to a government study, the Delta variant of COVID-19 is dominant in India and is behind the second wave of COVID in the country

Coronavirus Explained: What Are COVID Variants And Variants Of Concern?

New Delhi: Novel Coronavirus (SARS-CoV-2), the virus that causes COVID-19 disease among humans has evolved and mutated multiple times since it was first reported in China’s Wuhan in December, 2019. A mutation is a change in the genome or genetic sequence of a virus which results in a new strain of the virus. “This is a natural evolution and the virus is expected to change the more the virus circulates around”, said Dr Maria Van Kerkhove, WHO COVID-19 Technical Lead. But why DO some variants end up becoming ‘variants of concern’? How are ‘variants of concern’ different from ‘variants of interest’? How does WHO classify a variant as a variant of concern?

Experts answer all the questions on coronavirus and its variants.

Also Read: Coronavirus Strain Found In India, B.1.617 Named “Delta Variant”: WHO

What Is A Mutation?

SARS-CoV-2 coronaviruses share a genome that looks a little different from specimen to specimen. Each time a virus makes copies of itself, one or more of the letters in the genome can be written incorrectly. Coronaviruses are pretty good at proofreading, but mistakes still get through. This is how genetic mutations arise, and it’s all perfectly normal, explained Dr Sunil Jain, Head of emergency medicine at Jaslok Hospital and Research Centre.

Dr Jain further said that if a mutation makes it more difficult for the virus to replicate — for instance, if it results in a physical change that hampers its ability to get inside a host cell — that virus will die out and take the mutation along with it. But, if a mutation gives the virus a competitive advantage, it will spread more quickly than its rivals. That’s how some variants die out and some become ‘variants of concern.’

Also Read: B.1.617 Variant Of SARS-CoV-2 Drove Surge In The COVID-19 Cases In Last 2 Months

Variants Of Interest

Variants of interest (VOI) have properties, have mutations that have been identified that need further study, said Dr Kerkhove. As per WHO, variant becomes a ‘variant of interest’ when it has been identified to cause community transmission or multiple COVID-19 cases or clusters, or has been detected in multiple countries. Apart from this, a variant is assessed to be a VOI by WHO in consultation with the WHO SARS-CoV-2 Virus Evolution Working Group.

As per WHO’s latest update on May 31, there are six variants of interest –
– Epsilon and Iota both first found in the USA;
– Zeta, first reported in Brazil;
– Eta which has been found in multiple countries;
– Theta, first documented in samples from the Philippines;
– Kappa, a variant found in India.

Also Read: Delta Variant 60 Per Cent More Transmissible, Reduces Vaccine Effect: UK Experts

Variants Of Concern

Variants of concern have demonstrated changes. For example, you may have increased transmissibility, there may be a change in disease presentation or severity, or there may be a change in our ability to control the virus with public health and social measures, or the use of diagnostics, therapeutics and vaccines. So the recent variant of concern, the B.1.617, for example, has demonstrated increased transmissibility and this is why this has been classified as a variant of concern, explains Dr Kerkhove.

Alpha, Beta, Gamma, and Delta are the current four variants of concern. As per WHO, the Delta variant was first reported in India in October, 2020. As per the latest update from WHO, the Delta variant’s lineage B.1.617.2 is the only strain of concern at the moment. The UN health agency last month declared the entire strain a variant of concern but on June 1, it said only one of the sub-lineages deserved that label.

Also Read: Two Doses Of COVID Vaccine ‘Highly Effective’ In Reducing Hospitalisation From The Delta Variant: UK Analysis

Variants of High Consequence

A variant of high consequence has clear evidence that prevention measures or medical countermeasures (MCMs) have significantly reduced effectiveness relative to previously circulating variants, states the United States’ Centers for Disease Control and Prevention (CDC).

Possible attributes of a variant of high consequence include:
– demonstrated failure of diagnostics;
– evidence to suggest a significant reduction in vaccine effectiveness;
– a disproportionately high number of vaccine breakthrough cases;
– more severe clinical disease and increased hospitalisations.

As per CDC, currently, there are no SARS-CoV-2 variants that have risen to the level of high consequence.

Also Read: Delta Plus, New COVID Variant Identified, Experts Say No Cause Of Concern For Now

What Can One Do For Protection Against Coronavirus Variants?

Dr Kerkhove says that we need to do everything that we can to prevent infections and reduce the spread of the SARS-CoV-2 virus, whether it’s a virus variant, a variant of interest or a variant of concern or not, the SARS-CoV-2 virus can infect us and it can spread between people.

It means take all of the measures that you can to reduce your exposure in the possibility of you getting infected. It means physical distancing, avoiding crowded spaces, spending more time outdoors than indoors. If you are indoors, make sure that there’s good ventilation. It’s about having clean hands and wearing a mask properly over your nose and your mouth, practising respiratory etiquette, being well informed. And no matter what you do know what your risk is and take steps to lower your risk. And lastly, when it’s your turn, get vaccinated, said Dr Kerkhove.

WHO COVID-19 Technical Lead also informed that multiple studies are underway to study the nature of multiple variants in terms of transmissibility, severity and impact on diagnostics, therapeutics and vaccines. The current evidence suggests that vaccines and other control and diagnostics measures do work against the variants.

Also Read: Delta Plus Variant Of COVID-19 Is Not Yet ‘Variant Of Concern’, Nullifies Monoclonal Antibody Use: Government

NDTV – Dettol Banega Swasth India campaign is an extension of the five-year-old Banega Swachh India initiative helmed by Campaign Ambassador Amitabh Bachchan. It aims to spread awareness about critical health issues facing the country. In wake of the current COVID-19 pandemic, the need for WASH (WaterSanitation and Hygiene) is reaffirmed as handwashing is one of the ways to prevent Coronavirus infection and other diseases. The campaign highlights the importance of nutrition and healthcare for women and children to prevent maternal and child mortality, fight malnutrition, stunting, wasting, anaemia and disease prevention through vaccines. Importance of programmes like Public Distribution System (PDS), Mid-day Meal Scheme, POSHAN Abhiyan and the role of Aganwadis and ASHA workers are also covered. Only a Swachh or clean India where toilets are used and open defecation free (ODF) status achieved as part of the Swachh Bharat Abhiyan launched by Prime Minister Narendra Modi in 2014, can eradicate diseases like diahorrea and become a Swasth or healthy India. The campaign will continue to cover issues like air pollutionwaste managementplastic banmanual scavenging and sanitation workers and menstrual hygiene


Coronavirus has spread to 195 countries. The total confirmed cases worldwide are 22,70,55,138 and 46,70,253 have died; 18,97,86,461 are active cases and 3,25,98,424 have recovered as on September 17, 2021 at 5:36 am.


3,33,81,728 34,403Cases
3,25,98,424 37,950Recovered
4,44,248 320Deaths
In India, there are 3,33,81,728 confirmed cases including 4,44,248 deaths. The number of active cases is 3,39,056 and 3,25,98,424 have recovered as on September 17, 2021 at 2:30 am.

State Details

State Cases Active Recovered Deaths

65,11,525 3,595

52,893 310

63,20,310 3,240

1,38,322 45


44,46,228 22,182

1,86,754 4,559

42,36,309 26,563

23,165 178


29,65,191 1,108

16,202 282

29,11,434 808

37,555 18

Tamil Nadu

26,40,361 1,693

16,756 120

25,88,334 1,548

35,271 25

Andhra Pradesh

20,34,786 1,367

14,708 105

20,06,034 1,248

14,044 14

Uttar Pradesh

17,09,628 23

193 11

16,86,549 11

22,886 1

West Bengal

15,59,567 707

8,025 25

15,32,922 725

18,620 7


14,38,373 28

409 5

14,12,880 22

25,084 1


10,18,298 580

5,335 105

10,04,845 681

8,118 4


10,04,988 31

352 2

9,91,077 29



9,54,230 4

103 1

9,45,173 5



8,25,677 22

149 0

8,15,446 22


Madhya Pradesh

7,92,374 7

119 5

7,81,738 12



7,70,697 9

327 8

7,60,562 17



7,25,864 12

72 6

7,16,134 6



6,62,785 259

5,282 43

6,53,603 301

3,900 1


6,01,180 30

314 11

5,84,399 38

16,467 3


5,97,074 468

5,381 15

5,85,914 479

5,779 4


3,48,102 6

102 8

3,42,867 14



3,43,330 20

284 12

3,35,657 32


Jammu And Kashmir

3,27,466 170

1,421 72

3,21,630 98


Himachal Pradesh

2,16,430 127

1,568 82

2,11,215 206

3,647 3


1,75,183 95

699 1

1,71,195 96



1,25,170 107

963 63

1,22,380 42

1,827 2


1,17,913 216

2,614 7

1,13,478 219

1,821 4


83,787 31

427 26

82,553 56

807 1


78,958 229

1,804 140

75,784 86

1,370 3


76,591 1,121

13,888 85

62,449 1,202

254 4


65,168 4

31 2

64,319 2


Arunachal Pradesh

53,990 47

536 9

53,183 56



30,802 64

775 28

29,648 36



30,763 32

505 14

29,610 44

648 2


20,631 6

41 1

20,383 5


Dadra And Nagar Haveli


5 0





4 0



Andaman And Nicobar Islands

7,595 3

15 2

7,451 1


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