Research and analysis

Variants: distribution of case data, 14 January 2022

Updated 24 June 2022

Variants of concern or under investigation: data up to 12 January 2022

Surveillance overview

UK total distribution

Variant* Other names by which this variant may be known** Lineage Total confirmed (sequencing) and probable (genotyping) cases New cases since last update (data up to 5 January 2022)
Alpha VOC-20DEC-01 B.1.1.7 278, 359 +175
Beta§ VOC-20DEC-02 B.1.351 1,108§ -1
Gamma VOC-21JAN-02 P.1 284 0
Delta VOC-21APR-02 B.1.617.2 AY.1 AY.2 1,703,576†† +10,862
VUI-21OCT-01*** VUI-21OCT-01 A.Y 4.2 120,333 +1,584
Omicron VOC-21NOV-01 B.1.1.529 546,531 +181,155
Zeta VUI-21JAN-01 P.2 57 0
VUI-21FEB-03 VUI-21FEB-03 B.1.525 (previously designated UK1188) 513 -1
VUI-21FEB-04 VUI-21FEB-04 B.1.1.318 395 0
Theta VUI-21MAR-02 P.3 10 0
Kappa VUI-21APR-01 B.1.617.1 521 0
VUI-21APR-03 VUI-21APR-03 B.1.617.3 18 0
VUI-21MAY-02 VUI-21MAY-02 C.36.3 158 0
Lambda VUI-21JUN-01 C.37 8 0
Mu§ VUI-21JUL-01 B.1.621 59§ 0

*Information pertaining to VUI-21MAR-01, B1.324.1 with E484K has been removed as this variant has been reclassified as provisionally extinct. Variants VUI-21FEB-01 (A.23.1 with E484K), and VOC-21FEB-02 (Alpha with E484K) are provisionally extinct (not detected for 12 weeks in the UK or in GISAID) therefore they will no longer be included in the publication from 12 November 2021. Variant VUI-21MAY-01, AV.1 has been removed as of 3 December 2021 as it has been classified as provisionally extinct.

† Provisional results.

**WHO naming has been included where available.

†† Of which 727 had the K417N mutation.

Confirmed individuals are confirmed COVID-19 cases with a validated sequencing result meeting the confirmed case definitions outlined in the sections below. Probable individuals are confirmed COVID-19 cases with a genotyping result where sequencing confirmation is awaited or not available. Published figures include genotyping assay data for England, using a combination of highly specific mutations as an indicator of a probable variant. Genotyping assay data is currently only available for Alpha, Beta (for specimen dates up to and including 30 June 2021), Delta and Gamma.

§Due to having identical genotyping profiles, since 1 July Beta and Mu cases identified by genotyping have been categorised as ‘Beta or Mu’. In addition to the above numbers, a further 17 ‘Beta or Mu’ provisional genotyping cases have been identified.

***Confirmed VOC-21APR-02 with at least 2 VUI-21OCT-01 lineage defining positions called as alternate (variant) base and all other defining positions reported as N (unknown) or mixed bases.

Differences between a variant of concern and a variant under investigation

SARS-CoV-2 variants, if considered to have concerning epidemiological, immunological or pathogenic properties, are raised for formal investigation. At this point they are designated variant under investigation (VUI) with a year, month, and number. Following a risk assessment with the relevant expert committee, they may be designated variant of concern (VOC).

Changes in nomenclature

The previous variant names frequently include similar numbers with similar or repeating patterns. This makes referring to them verbally challenging. To overcome this challenge, a revised nomenclature has been agreed involving dropping the first 2 numbers of the year and replacing the 2-month numbers with a 3-letter abbreviation. This shortens the name and reduces the degree of repeated sequences of numbers. The table containing surveillance overview ‘UK total distribution’ contains a list of new variant names alongside previous or other names in use for VOCs and VUIs.

Alpha

Surveillance overview

This variant was first detected in the UK and was first sequenced in the UK in September 2020.

Total confirmed and probable cases
England 227,626
Northern Ireland 9,135
Scotland 29,130
Wales 12,468
Total cases 278,359

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with at least 5 VOC-20DEC-01 lineage defining positions are called as alternate (variant) base and all other defining positions reported as N (unknown) or mixed bases
Probable (genotyping) COVID-19* confirmed case with a genotyping result where sequencing confirmation is awaited or not available
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Beta

Surveillance overview

This variant was first sequenced in the UK in December 2020.

Total confirmed and probable cases
England 994
Northern Ireland 9
Scotland 62
Wales 43
Total cases 1,108

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case where:
• at least 4 VOC-20DEC-02 lineage defining positions are called as alternate (variant) base, and
• all other defining positions reported as N (unknown) or mixed bases 
or
• at least 5 of the 9 non-synonymous changes
Probable (genotyping) COVID-19* confirmed case with a genotyping result where sequencing confirmation is awaited or not available
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Gamma

Surveillance overview

This variant was first detected in the UK in February 2021.

Total confirmed and probable cases
England 259
Northern Ireland 0
Scotland 23
Wales 2
Total cases 284

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with:
• at least 5 lineage defining non-synonymous changes called as alternate base, and
• all other positions either N or mixed bases
Probable (genotyping) COVID-19* confirmed case with a genotyping result where sequencing confirmation is awaited or not available
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Delta

Surveillance overview

Total confirmed and probable cases
England 1,386,741
Northern Ireland 93,028
Scotland 133,011
Wales 90,796
Total cases 1,703,576

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with at least 4 variant defining changes called as alternate base
Probable (genotyping) COVID-19* confirmed case with a genotyping result where sequencing confirmation is awaited or not available
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

VUI-21OCT-01

Surveillance overview

Total confirmed and probable cases
England 91,473
Northern Ireland 734
Scotland 13,335
Wales 14,791
Total cases 120,333

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case that is confirmed VOC-21APR-02 with at least 2 VUI-21OCT-01 lineage defining positions called as alternate (variant) base and all other defining positions reported as N (unknown) or mixed bases.
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Omicron

Surveillance overview

Total confirmed and probable cases
England 457,817
Northern Ireland 31,051
Scotland 32,639
Wales 25,024
Total cases 546,531

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with at least 10 lineage defining non-synonymous changes called as alternate base and no more than 7 defining positions called as wild-type
Probable (genotyping) COVID-19* confirmed case with a genotyping result where sequencing confirmation is awaited or not available
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).  

Zeta

Surveillance overview

This variant first sequenced in the UK in November 2020.

Total confirmed and probable cases
England 51
Northern Ireland 0
Scotland 5
Wales 1
Total cases 57

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* case confirmed as infected with VUI-21JAN-01 through whole genome sequencing (WGS) where:
• results of all lineage defining non-synonymous changes called as alternate base
or
• 6 of 7 non-synonymous changes called as alternate base, and
• remaining position either N or mixed bases
Probable (genotyping) COVID-19* confirmed case with a genotyping result where sequencing confirmation is awaited or not available
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

VUI-21FEB-03

Surveillance overview

This variant was first detected in the UK in December 2020.

Total confirmed and probable cases
England 461
Northern Ireland 2
Scotland 40
Wales 10
Total cases 513

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with:
• at least 5 lineage defining non-synonymous changes called as alternate base, and
• all other positions either N or mixed bases
Probable (genotyping) COVID-19* confirmed case with a genotyping result where sequencing confirmation is awaited or not available
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

VUI-21FEB-04

Surveillance overview

This variant was first detected in the UK (England).

Total confirmed and probable cases
England 344
Northern Ireland 40
Scotland 11
Wales 0
Total cases 395

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with:
• at least 5 lineage defining non-synonymous changes called as alternate base, and
• all other positions either N or mixed base
or
• at least 5 of the 9 non-synonymous changes
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Theta

Surveillance overview

Total confirmed and probable cases
England 7
Northern Ireland 0
Scotland 3
Wales 0
Total cases 10

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with:
• at least 7 variant defining changes called as alternate base, and
• all other positions either N or mixed base
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Kappa

Surveillance overview

Total confirmed and probable cases
England 475
Northern Ireland 4
Scotland 27
Wales 15
Total cases 521

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with:
• at least 6** variant defining changes called as alternate base, and
• all other positions either N or mixed base
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).
**Due to overlap with Delta sequences, the case definition of Kappa sequences was changed on 27 August 2021.

VUI-21APR-03

Surveillance overview

Total confirmed and probable cases
England 15
Northern Ireland 0
Scotland 0
Wales 3
Total cases 18

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with:
• at least 8 variant defining changes called as alternate base, and
• all other positions either N or mixed base
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

VUI-21MAY-02

Surveillance overview

Total confirmed and probable cases
England 147
Northern Ireland 3
Scotland 4
Wales 4
Total cases 158

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with at least 5 variant defining changes called as alternate base, and
• all other positions either N or mixed base.
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Lambda

Surveillance overview

Total confirmed and probable cases
England 8
Northern Ireland 0
Scotland 0
Wales 0
Total cases 8

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with at least 5 VUI-21JUN-01 lineage defining positions are called as alternate (variant) base and all other defining positions reported as N (unknown) or mixed bases.
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).

Mu

Surveillance overview

Total confirmed and probable cases
England 53
Northern Ireland 2
Scotland 3
Wales 1
Total cases 59

Case definitions

Genomic match Criteria
Confirmed
(sequencing)
COVID-19* confirmed case with at least 5 VUI-21JUL-01 defining mutations called as alternate (variant) base and all other defining positions reported as N (unknown) or mixed bases.
*A confirmed COVID-19 case: a case where the individual is confirmed to be infected with SARS-CoV-2 by polymerase chain reaction (PCR).