Variant Surveillance Analysis Report: BA.2.86
This report shares detailed variant surveillance analyses contributing to the risk assessments and designation of new SARS-CoV-2 variants. It contains early data and analysis on emerging variants, with a high level of uncertainty. The data used in this report is cut-off at 4 September 2023 to allow for analyses.
Situational Assessment BA.2.86
- Continued slow accumulation of cases globally, including new countries.
- Rate of detection of new sequenced cases cannot be used as an indicator of growth due to limited genomic surveillance.
- BA.2.86 is globally dispersed, possibly due to international seeding from unknown sources through mass travel.
- Data suggests established community transmission of BA.2.86 within the UK.
- BA.2.86 does not have confirmed growth advantage within the UK compared to other variants.
- A care home outbreak of BA.2.86 indicates potential transmissibility in close contact settings.
- Pseudovirus neutralisation data shows consistency with mutational profile.
- Increasing COVID-19 transmission in the UK noted, with various contributing factors.
- Insufficient number of cases to assess outcome or severity.
Data Summary BA.2.86
As of 4 September 2023, there are 34 BA.2.86 sequenced cases in England, with cases reported in the East of England, London, and North West England. Of these cases, 5 were hospitalized and no deaths due to COVID-19 have been reported. Scotland, Wales, and Northern Ireland have not reported any cases of BA.2.86. Globally, 33 sequences from human cases have been identified across 9 countries.
Change to Genomic Data Upload Procedures
Starting from 5 September 2023, the lag for uploading UK sequencing data to global databases has been reduced from 7 days to 72 hours to enable faster sharing while ensuring quality and data checks.
Variant Prevalence (UKHSA-Designated Variants)
For sequences with specimen dates between 14 August 2023 and 20 August 2023, V-22OCT-02 (XBB) accounted for 24.8% of UK sequences, followed by V-23JUL-01 (EG.5.1) at 23.3%, V-23APR-01 (XBB.1.16) at 19.5%, V-23JAN-01 (XBB.1.5) at 5.8%, and V-22DEC-01 (CH.1.1) at 1.5%. The remaining sequences (25.1%) were either unassigned variants or of insufficient quality.
Variant designations are made when variants are considered significant enough for routine surveillance. EG.5.1 and BA.2.86 have been designated as V-23JUL-01 and V-23AUG-01 respectively. FL.1 and FY.4.1 have been added to the signals under monitoring due to growth or significant mutational profiles.
Based on English sequencing data, only XBB.1.16.6 and XBB.2.3.11 have positive growth rates relative to other lineages. BA.2.86 did not meet the criteria for analysis.
- BA.2.86 was first identified on 14 August 2023 due to a large number of mutations in international sequences.
- Currently, there are 34 confirmed cases in England, including a care home outbreak in the East of England.
- No deaths have been reported among these cases, but hospitalization has been observed.
Care Home Outbreak
An outbreak in a care home in the East of England was reported on 21 August 2023. Increased number of cases and severity were observed compared to previous outbreaks in care homes. Further investigation is underway.
While BA.2.86 shows potential transmissibility in close contact settings, further monitoring and assessment are needed to understand its impact and severity. Ongoing surveillance and data analysis will provide more insights into the variant’s characteristics and spread.