While there is much we still don't know about the emerging BA.2.86 variant (most importantly, how much of an impact it will have on infections, hospitalizations, or deaths), it is fair to say it represents the largest genetic leap in the SARS-CoV-2 virus since Omicron arrived in late 2021.
Within a few of months of its detection (Nov 2021), Omicron had all but supplanted the dominant Delta variant - sparking a massive global surge in cases - but was thankfully less deadly (at least, in a largely vaccinated population) than its predecessors.
As a result, the world has decided the COVID threat is over, and for the most part has stopped reporting on cases, hospitalizations and deaths. Equally troubling, testing for variants has declined significantly both here in the United States (see Nowcast map below), and around the world.
For now, it remains unknown how disruptive BA.2.86 will become in the months ahead. It may be a flash in the pan, and end up being trampled by the crowded viral field. Or it could be - like Omicron before it - the start of a new phase for COVID.
Only time will tell.
But it does answer one very important question. New, and radically different COVID variants can still emerge. Which means we dismantle our surveillance and reporting systems at our own peril.
Over the past three days we've seen statements from the WHO and Denmark's SSI on BA.2.86. Late yesterday afternoon, the UK's Health Security Agency issued the following two reports.
UKHSA publishes risk assessment for BA.2.86
The UK Health Security Agency (UKHSA) has published an initial risk assessment of the SARS-CoV-2 variant BA.2.86. This variant was detected in the UK on Friday 18 August, and has also been identified in Israel, Denmark and the US. It has been designated as V-23AUG-01 for the purpose of UKHSA monitoring.The newly identified variant has a high number of mutations and is genomically distant from both its likely ancestor, BA.2, and from currently circulating XBB-derived variants. There is currently one confirmed case in the UK in an individual with no recent travel history, which suggests a degree of community transmission within the UK. Identifying the extent of this transmission will require further investigation.
There is currently insufficient data to assess the relative severity or degree of immune escape compared to other currently-circulating variants.
Dr Meera Chand, Deputy Director, UKHSA said:
V-23AUG-01 was designated as a variant on 18 August 2023 on the basis of international transmission and significant mutation of the viral genome. This designation allows us to monitor it through our routine surveillance processes.
We are aware of one confirmed case in the UK. UKHSA is currently undertaking detailed assessment and will provide further information in due course.
UKHSA will continue to monitor the situation closely and will publish the results of our analysis when they are available.
Research and analysis
Risk assessment for SARS-CoV-2 variant V-23AUG-01 (or BA.2.86)
Updated 18 August 2023
Part 1. Context and UK case
As of 3 pm, 18 August 2023, 6 unrelated cases of a new variant BA.2.86 have been identified in 4 countries. This variant is notable due to a high number of mutations.
Israel published the first genome on 13 August 2023. Subsequently Denmark has identified 3 cases, and a single case has been identified in both the US and the UK.
The UK case was identified in a patient tested at a London hospital on 13 August 2023, with no recent travel history. The sample was sequenced routinely as part of local hospital based genomic research.
Part 2. Variant technical group assessment
Meeting and assessment 1 pm, 18 August 2023.
- The newly identified variant BA.2.86 has a high number of mutations and is distant from both its likely ancestor BA.2 and also currently circulating XBB-derived variants.
- Despite the small number of sequences, the appearance of the variant rapidly in multiple countries which are still operating genomic surveillance, in individuals without travel history, suggests that there is established international transmission.
- The sequences are similar across the world, potentially suggestive of a relatively recent emergence and rapid growth, but this is a low confidence assessment until further sequences are available.
- The UK case has no recent travel history, also suggesting a degree of community transmission within the UK. This clinical site sequenced data rapidly locally, and data from surveillance systems from the same period is likely to follow, thus a more complete assessment of UK transmission will be possible in 1 to 2 weeks.
- It is unreliable to attempt to predict the combined effect of the large number of mutations, however there is sufficient information to expect significant antigenic change. There are also mutations in spike which may be associated with changes in other viral properties.
- At present the UK Health Security Agency (UKHSA) has designated this a variant for the purposes of tracking and assessment (V-23AUG-01). We will consider as signals of escalating concern the presence of phenotypic data confirming significant immune escape, other relevant phenotypic data, and signals of rapidly changing epidemiology in the UK or other countries where the variant has been detected.
- UKHSA will share data from surveillance systems, variant growth rates, and phenotypic laboratory data when available. It is not possible to assess comparative severity by variant based on UK surveillance at present.
We should know a lot more about BA.2.86 in the next week or two, now that it has captured the world's attention. Hopefully, this is much ado about nothing.
But even if we get lucky, COVID still has the ability to deliver new surprises.
Stay tuned.
