ECDC de-escalates BA.2, BA.4 and BA.5 from its list of variants of concern
As of 3 March 2023, ECDC will de-escalate BA.2, BA.4 and BA.5 from its list of SARS-CoV-2 variants of concern (VOC), as these parental lineages are no longer circulating. ECDC will continue to categorise and report on specific SARS-CoV-2 sub-lineages in circulation that are relevant to the epidemiological situation.
ECDC categorised Omicron (B.1.1.529) as a VOC in November 2021 on the basis that this variant was predicted to have a substantial negative impact on the COVID-19 epidemiological situation in the EU/EEA—Omicron was the most highly mutated SARS-CoV-2 variant to-date, with substantial immune escape capabilities relative to prior SARS-CoV-2 variants. Omicron quickly established itself as the dominant SARS-CoV-2 lineage globally, resulting in a surge of COVID-19 cases.
In early 2022, a large number of Omicron-descendent sub-lineages emerged (BA.1, BA.2, BA.3, BA.4, BA.5), with ECDC categorising these sub-lineages separately to better distinguish their relative impacts to the epidemiological situation. Amongst these sub-lineages, BA.2, BA.4 and BA.5 consistently circulated in the EU/EEA until late 2022.
The current epidemiological situation is hallmarked by a highly diverse landscape of co-circulating BA.2 and BA.5 descendent variants, which have different properties to their parental lineages and require individual assessment. ECDC currently lists the most prominent amongst these under the categories ‘variant of interest’ (VOI) and ‘variant under monitoring’ (VUM):
Variant of interest (VOI)
- BQ.1 (BA.5 descendent)
- BA.2.75 (BA.2 descendent)
- XBB (BA.2.10.1 / BA.2.75 descendent)
- XBB.1.5 (BA.2.10.1 / BA.2.75 descendent) new VOI
Variant under monitoring (VUM)
- BF.7 (BA.5 descendent)
- BA.2.3.20 (BA.2 descendent)
- CH.1.1 (BA.2.75 descendent)
- BN.1 (BA.2.75 descendent)
- XBC (Delta (21I) / BA.2 recombinant)
- XAY (Delta (AY.45) / BA.2 recombinant)
The absence of SARS-CoV-2 variants categorised as ‘of concern’ reflects the current stable epidemiological situation in the EU/EEA. However, it does not signal the end of the threat posed by SARS-CoV-2 and possible future variants that may emerge.
Recommendations for public health authorities
ECDC encourages countries to remain vigilant, by reinforcing representative surveillance systems, sequencing capacity, and reporting, as outlined in the July 2022 guidance Operational considerations for respiratory virus surveillance in Europe and most recent COVID-19 surveillance reporting protocols.
Establishing strong and sustainable respiratory virus surveillance in the community will be critical moving forward to reliably assess the relative contribution of different SARS-CoV-2 variant threats to the EU/EEA.
Information for the wider public
Members of the public are encouraged to remain mindful of the continued risk of respiratory infections caused by SARS-CoV-2, influenza and other respiratory viruses with a risk of severe outcomes, particularly during winter months. Maintaining respiratory hygiene practices are extremely important for limiting transmission and individuals should self-isolate whilst experiencing respiratory symptoms. Vaccination is recommended, in accordance with national policies, as the primary measure for protection against severe outcomes for COVID-19 and influenza.