Threat Assessment Brief: Emergence of SARS-CoV-2 B.1.617 variants in India and situation in the EU/EEA
The aim of this Threat Assessment Brief is to assess potential public health implications of B.1.617 variants for EU/EEA countries, with a focus on lineage B.1.617.2.
On 24 May, ECDC upgraded B.1.617.2 to a variant of concern, after new information became available on increased transmissibility and some impact on vaccine effectiveness, especially after one vaccine dose. The suggestions highlighted in the Threat Assessment Brief regarding options for response remain valid, particularly vaccination rollout as a high priority to reduce COVID-19 mortality by vaccinating those at risk of severe illness in the shortest time possible.
- First reported in India in December 2020, SARS-CoV-2 lineages B.1.617.1, B.1.617.2 and B.1.617.3 have been increasingly detected in other countries.
- The aim of this Threat Assessment Brief is to assess the potential public health implications of the B.1.617 lineages for EU/EEA countries with a focus on lineage B.1.617.2.
- Over the past eight weeks India and some surrounding countries have seen a sharp increase in the number of reported SARS-CoV-2 cases and deaths. This has been associated with a rising proportion of sequenced viruses belonging to lineages B.1.617.1 and B.1.617.2.
- The United Kingdom has seen a rapid increase in detection of lineage B.1.617.1 and, to a greater extent, B.1.617.2, associated with travel to India and onward community transmission. On the 6 May, the United Kingdom (UK) designated lineage B.1.617.2 as a variant of concern.
- In the EU/EEA there are indications that the frequency of detection of both lineages B.1.617.1 and B.1.617.2 is increasing.
- Currently described lineages B.1.617.1, B.1.617.2 and B.1.617.3 have distinct mutation profiles and warrant individual assessment. Given the still very limited available data with respect to their transmissibility, disease severity and immune escape potential relative to other co-circulating SARS-CoV-2 variants in the EU/EEA, the full impact of these lineages on public health is not yet possible to assess.
- At this time, ECDC maintains its assessment of B.1.617.1, B.1.617.2 and B.1.617.3 as variants of interest and will continue to actively monitor the situation.
Options for response
- In order to better understand and inform assessments of the potential public health implications of these variants, targeted genomic surveillance should be enhanced (including of travel-associated cases, clusters or outbreaks and breakthrough infections) together with antigenic characterisation of SARS-CoV-2 variants and enhanced general surveillance.
- Diagnostic laboratories should remain vigilant to detect any mismatches of specific RT-PCR assay primers and probes in comparison to circulating virus genomes.
- COVID-19 vaccination rollout should continue to be a high priority to reduce COVID-19 mortality by vaccinating those at risk of severe illness in the shortest time possible, thereby reducing SARS-CoV-2 transmission, as has recently been documented in Israel and the UK.
- COVID-19 vaccine coverage remains at low levels in all EU/EEA countries, and as such, ECDC currently advises caution in the relaxation of current non-pharmaceutical measures including those related to travel. The limited information so far regarding these new variants does not change ECDC’s current advice on nonpharmaceutical measures. Greater understanding of the risks related to these B.1.617 lineages is needed before any modification of current measures can be considered.
- Further characterisation of these lineages is needed to allow a full assessment of their potential public health implications
Note: Since the publication of the Threat Assessment Brief, WHO categorised B.1.617.1, B.1.617.2 and B.1.617.3 as variants of concern. More details about their assessment can be accessed in their 11 May 2021 Weekly Epidemiological Update.
Updated assessment on all variants of concern
SARS-CoV-2 variants of concern as of 26 January 2023
ECDC regularly assesses new evidence on variants detected through epidemic intelligence, rules-based genomic variant screening or other scientific sources.