SARS-CoV-2 variants of concern as of 30 September 2021

ECDC regularly assesses new evidence on variants detected through epidemic intelligence, rules-based genomic variant screening, or other scientific sources. If a decision is made to add, remove, or change the category for any variant, the tables are updated to reflect this change. The tables are regularly sent for consultation to ECDC and WHO Regional Office for Europe’s joint virus characterisation working group. The rules-based genomic screening is performed using an open source algorithm. The weekly ECDC variant surveillance data report can be found in the weekly COVID-19 country overviews published on ECDC’s website. On 10 June 2021 ECDC published “Rapid Risk Assessment: Assessing SARS-COV-2 circulation, variants of concern, non-pharmaceutical interventions and vaccine rollout in the EU/EEA, 15th update” and on 23 June 2021 “Threat Assessment Brief: Implications for the EU/EEA on the spread of the SARS-CoV-2 Delta (B.1.617.2) variant of concern”.

Description of the tables

The tables include:

Category: variant of concern (VOC), variant of interest (VOI), or variant under monitoring (see definition above each table).

  1. WHO label: As of 31st May 2021, WHO proposed labels for global SARS-CoV-2 variants of concern and variants of interest to be used alongside the scientific nomenclature in communications about variants to the public. This list includes variants on WHO’s global list of VOC and VOI, and is updated as WHO’s list changes.
  2. Lineage and additional mutations: the variant designation specified by one or more Pango lineages and any additional characteristic spike protein changes. An alternate description may be used if the variant is not easy to describe using this nomenclature. For updated information on Pango lineages and definition of lineages and for instructions on how to suggest new lineages, visit the Pango lineages website. Each lineage in the table is linked to the respective lineage page on the Pango lineages website.
  3. Country first detected: only present if there is moderate confidence in the evidence relating to the first country of detection.
  4. Spike mutations of interest: not all spike protein amino acid changes are included – this is not a full reference for assignment of the variants. It includes changes to spike protein residues 319-541 (receptor binding domain) and 613-705 (the S1 part of the S1/S2 junction and a small stretch on the S2 side), and any additional unusual changes specific to the variant.
  5. Year and month first detected: as reported in the GISAID EpiCoV database. This can be adjusted backwards in time if new retrospective detections are made.
  6. Evidence concerning properties in three different categories:
    • Transmissibility
    • Immunity
    • Infection severity
      The evidence is annotated to indicate whether it is derived from the variant itself (v) or from mutations associated with the variant (m). Evidence that is deemed “low confidence” is annotated to indicate that it is unclear. An empty field means that we have not yet found and evaluated any scientific evidence for the category, while “no” indicates evidence that there is no change associated with the property. The comparator virus assumed “wild-type’” is B.1 (with D614G and no other spike protein changes).
  7. Transmission in the EU/EEA: categorised as dominant, community, outbreak(s), and sporadic/travel. The categories are qualitative, and the assessment is based on surveillance data collected in TESSy, GISAID EpiCoV data, epidemic intelligence data, and direct communications with the affected countries.

Variants of Concern (VOC)

For these variants, clear evidence is available indicating a significant impact on transmissibility, severity and/or immunity that is likely to have an impact on the epidemiological situation in the EU/EEA. The combined genomic, epidemiological, and in-vitro evidence for these properties invokes at least moderate confidence. In addition, all the criteria for variants of interest and under monitoring outlined below apply.


All sub-lineages of the listed lineages are also included in the variant, e.g., AY.1 is included in Delta as it is a sub-lineage of B.1.617.2.

Variants of interest (VOI)

For these variants, evidence is available on genomic properties, epidemiological evidence or in-vitro evidence that could imply a significant impact on transmissibility, severity and/or immunity, realistically having an impact on the epidemiological situation in the EU/EEA. However, the evidence is still preliminary or is associated with major uncertainty. In addition, all the criteria for variants under monitoring outlined below apply.

n/a: not applicable, no WHO label has been assigned to this variant at this time

All sub-lineages of the listed lineages are also included in the variant, e.g., C.37.1 is included in Lambda as it is a sub-lineage of C.37.

Variants under monitoring

These additional variants of SARS-CoV-2 have been detected as signals through epidemic intelligence, rules-based genomic variant screening, or preliminary scientific evidence. There is some indication that they could have properties similar to those of a VOC, but the evidence is weak or has not yet been assessed by ECDC. Variants listed here must be present in at least one outbreak, detected in a community within the EU/EEA, or there must be evidence that there is community transmission of the variant elsewhere in the world.

n/a: not applicable, no WHO label has been assigned to this variant at this time

All sub-lineages of the listed lineages are also included in the variant, e.g., AZ.1 is included in B.1.1.318 as it is a sub-lineage of it.

De-escalated variants

These additional variants of SARS-CoV-2 have been de-escalated based on at least one the following criteria: (1) the variant is no longer circulating, (2) the variant has been circulating for a long time without any impact on the overall epidemiological situation, (3) scientific evidence demonstrates that the variant is not associated with any concerning properties.

n/a: not applicable, no WHO label has been assigned to this variant at this time

All sub-lineages of the listed lineages are also included in the variant, e.g., B.1.429.1 is included in B.1.427/B.1.429 as it is a sub-lineage of B.1.429.

(a) No assessment of transmission is given for variants in the monitoring category, only detected/not detected.

(b) The earliest detections from several different countries are close in time and there is no clearly demonstrated travel link to a specific country that explains the detections.

(c) The property of concern for this variant was the fact that there are reports of difficulties associated with detecting it in upper respiratory tract samples. These difficulties were not caused by primer-template mismatch but rather by the virus not being present in sufficient quantities in the upper respiratory tract.

The report is taken from https://www.ecdc.europa.eu/

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