I imagine some rather awkward discussions are taking place in Downing Street right now…
@RishiSunak @UKHSA @SteveBarclay @SRileyIDD
Once again, newspapers in the UK are filled with stories about a new Covid variant that’s suddenly causing cases to surge at a very rapid rate in India:
This is XBB.1.16, also known as ‘Arcturus’…
📍Covid cases are increasing at a rapid rate in India, with cases doubling every 5-6 days.
📍Wastewater surveillance in Bengaluru (a Southern India capital city) indicates that Covid levels in that area have just soared to the highest level since the start of pandemic.
It’s still early days for the XBB.1.16 variant in India so the country-wide case numbers cannot be compared to the peaks of other big waves - it is the rapid exponential growth which is the big concern here…
Many people don’t truly understand the implications of exponential growth.
The problem is that, if something is doubling at a constant rate, the first few doublings don’t make a lot of difference…
But then… whoosh! 
1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048…
Doctors in India have warned:
“The XBB 1.16 variant is the primary cause of the rise in cases. This variant is showing immune escape & is able to evade the immune system. It is infecting those who had the Covid infection during previous waves.”
msn.com/en-in/health/m…
XBB.1.16 (‘Arcturus’) is very similar to the XBB.1.5 variant (the ‘Kraken’, previously the most transmissible COVID variant).
But some additional mutations have made it even more infectious…
A study from Japan has just been released showing that XBB.1.16 (‘Arcturus’) has the potential to spread ~30% more efficiently than its parental variant XBB.1 and ~20% more than XBB.1.5 (the ‘Kraken’).
It is thought to be the most infectious variant yet.
But XBB.1.16 (‘Arcturus’) is not just in India… it’s already been detected in many other countries around the world.
And it’s been in the U.K. for at least a month.
(Note: the last 2 weeks’ worth of data are incomplete and will be adjusted upwards as more data comes through).
In the US, they’re already starting to see the beginnings of exponential growth for XBB.1.16, with CDC Nowcast estimates for this variant more than doubling in the last week, from 3.4% to 7.2%…
It would be great to have visibility of what’s happening here in the UK…
However unfortunately, the arrival of Arcturus coincided almost perfectly with the axing of the ONS Infection Survey 🤦🏻♀️
This survey was the gold standard, the envy of the world.
independent.co.uk/news/health/co…
The beauty of ONS Covid infection Survey is that it was based on a random sample of households to provide a nationally representative survey.
This means it provided an unbiased estimate which was independent of how many people were testing themselves.
ons.gov.uk/peoplepopulati…
But sadly the survey was stopped just as Arcturus reached our shores… and just as Covid cases rose to the highest point so far this year.
The final ONS Infection survey indicated that 1 in 40 people were infected. That’s higher than in Jan 2021 when we went into lockdown!
Since then, with the new financial year upon us and Covid budgets slashed, we have entered a brave (or stupid) new world…
…the world of the data vacuum.
There is now NO reliable source of data for tracking Covid prevalence in the UK.
“Hang on, can’t we just look at Covid hospitalisation figures?” you may ask…
Sadly not. At the same time as stopping the ONS Infection Survey, big changes to Covid testing guidance in hospitals was also announced…
So Covid hospitalisation data is no longer reliable either👇🏻
“Surely we must still be doing genomic sequencing in the UK?”
Well yes, but since testing ended in hospitals, sample sizes have plummeted.
Last week, four XBB.1.16 samples were sequenced from a total of just 666.
A few months ago, we were typically doing 5,000 samples a week.
We do still have the Zoe Study which is modelled based on self-reported Covid test results from their user base.
But with self-testing dwindling to a trickle and no ONS Survey to optimise their algorithm against, I have doubts about how reliable this will be going forward…
Just a few weeks ago,
@mvankerkhove from the WHO gave an update on XBB.1.16 and stressed how important is is for countries to *strengthen* their surveillance systems of covid-19.
So why have we done the complete opposite?
We are flying completely blind now.
Meanwhile, India has been able to use their Covid surveillance as an early warning system to identify this incoming new wave and take action.
They’ve put hospitals on red alert & warned them to start preparing for potential surges in hospitalisations.
bbc.co.uk/news/world-asi…
The Welsh government have issued a written statement expressing their deep disappointment and concern about the UK government deciding to discontinue the ONS Infection Survey, given the importance of this surveillance study 👇🏻
…but at least Wales had the foresight to get their Covid wastewater surveillance up and running so at least they have something to fall back on. 💩
Meanwhile, our Covid wastewater surveillance ended over a year ago.
So we are left wallowing in a complete data vacuum.
Come on @UKHSA, this must be a tad embarrassing now…
I’m sure many stakeholders are knocking at your door to enquire what the XBB.1.16 situation is like in the UK right now…
How do you tell them that you have absolutely no surveillance now?
When are you going to fix this?!
…and for anyone who is fed up of hearing about Covid and thinks all this is nothing to worry about, this thread is just for you 👇🏻
EDIT: I will keep adding to this thread as new information about the XBB.1.16 (‘Arcturus’) variant arises…
Some people have been downplaying the risks posed by XBB1.16 by saying that it may be no more severe than previous omicron variants.
We have limited data on its severity but we *do* have evidence that it’s ~20% more transmissible than the previous most transmissible variant.
A more transmissible variant (with the same severity) is still a very big issue.
Here’s why:
A 50% more transmissible variant will cause significantly more deaths than a 50% more severe strain because it will scale on an exponential growth curve instead of a linear curve.
Meanwhile, in Delhi (India), the exponential growth curve has been busy doing its thing:
📍Almost half of households in Delhi have one or more family member unwell.
📍 Test positivity rates in Delhi have shot up to over 32%.
ndtv.com/delhi-news/del…
Here in the UK, we’re now starting to see early signs of exponential growth of the XBB.1.16 (‘Arcturus’) variant from the small number of Covid tests that are still being sequenced.
Beyond this, we are pretty much flying blind, in a complete data vacuum...
With these early warning signs of exponential growth, it would be great to have some proper Covid surveillance back in place right about now…
How about it, @UKHSA ?
If you don’t want to take my word for it, please listen to the advice of the World Health Organisation.
👇🏻
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