Bottom line, Im not worried, but it is interesting

VOCs

What is XE?

https://assets.publishing.service.gov...

https://deadline.com/wp-content/uploa...

XE strain is a recombinant variant of BA.1 and BA.2

Mutation

An error is incorporated in the viral genome

Recombination

Coinfecting viruses exchange genetic information, creating a novel virus

Changes to variant classification system

Variant of Concern label

a detrimental change in biological properties (changes in transmissibility, severity or immune evasion) compared to the current dominant variant(s); and

a growth rate potentially compatible with maintaining transmission and/or displacing the current dominant variant.

designate new variants based on genomic features and growth

X = BA.1
E = BA.2
X = Delta
F = Delta

Two are a combination of Delta and BA.1

XD and XF

XD, few cases detected in France, Belgium, Denmark

XT, small cluster detected in UK, (before 15th Feb)

One recombination of BA.1 and BA.2

XE is a BA.1/BA.2 recombinant

XE evidence of community transmission within England
currently less than 1% of total sequenced cases

Using the most recent data up to 16 March 2022

XE has a growth rate 9.8% above that of BA.2

Per week

XE biology

763 XE sequences in the UK data

XE is a BA.1 and BA.2 recombinant

3 mutations that are not present in all BA.1 or BA.2 sequences

BA.2 latest

SGTP is a reasonable proxy for BA.2

England on 20 March 2022, 93.7% BA.2

England on 6th March 2022, 82.6% BA.2

Growth rate of BA.2

Increased growth rate compared to BA.1 in all regions of England

Growth rate, 75% greater relative growth for BA.2 compared to BA.1.

GR = 0.753 per week

Hospitalisation

No evidence of a greater risk of hospitalisation following infection with BA.2 compared to BA.1.

SARS-CoV-2 Immunity and Reinfection EvaluatioN (SIREN)

90 day gap

N = 44,000 healthcare workers, recruited from 135 sites

Now highly vaccinated (more than 95%)

Two weekly PVR testing


27th December 2021 to 16th January 2022

N = 496,228 cases of PCR confirmed SARS-CoV-2 infection

186,896 BA.1 confirmed cases with genome sequencing
Thirty-one of these cases had another subsequent sequenced

but there are no early indications of a specific reinfection issue with this scenario.