Yesterday I questioned if the track and trace methods that have been used are able to identify all transmissions that occur via aerosol transmission. This thread explains why I think it has let us down and the implications of this for us all. A thread: 🧵1/23
Listed are what are deemed to be close contacts by the T&T teams as found on the Welsh Government’s website. Do you think these are enough to pick up all possible cases of aerosol transmission? 2/23
I ask the question not to criticise the tireless work that’s been done by contact tracers across the country, but rather to raise awareness of 2 things:
1. T&T is far from perfect (accuracy is dependent on honesty and good memory from traced individuals tells us this)
And... 3/23
2. My main point which is that information gleaned from T&T informs government- it’s incredibly important and relevant to everyone, as it justifies the rationale for removing our individual freedoms. So it better be reflective of what’s going on, right?

4/23
We won’t get out of this through vaccines alone.
We need every measure in place to mitigate transmission-
social distancing: ✅
Mask wearing: ✅
Hand hygeine: yes, go on then ✅
But the one we’re yet to grasp properly...

...Reduce airborne transmission 5/23
H/t @Don_Milton
(If you remain unsure of masks, which I totally get as I remember being unsure of their potential benefit, then please take a look at this really cool website. 6/23
nytimes.com/interactive/20… )
So understanding how the virus spreads is CRUCIAL, and politicians should look beyond what the track and trace data is telling us- it’s incredibly unwise not to do so. Over the weekend one member of the Senedd revealed to me that she’d fallen foul to this: 7/23
Whether I managed to convince them of their error only they can answer, but it does trouble me that after a year of restrictions, what is accepted as truth in terms of transmission has STILL not sunken in and been understood by those who are representing us 8/23
Track and trace methods was based on assumptions made about how the virus spread. The truth is the virus spreads in an overdispersed manner, that is, it tends to spread in clusters.
This link by @ScienceMagazine explains it really well, take a look: 9/23

vis.sciencemag.org/covid-clusters/
We refer to this dispersal as being the K number. While the better known R number represents the average number of people a single infected person will go on to infect, the K number highlights that not all infected individuals will go on to infect the same number of people. 10/23
This is incredibly important, because if the K number is low, it means the virus spreads in clusters. We’ve learnt what behaviours and environments are most risky, but this hasn’t come from run-of-the-mill T&T, it’s come from international research! 11/23
Methodology used by T&T until recently was something called ‘forward tracing’, whereby those people the infected person came into the contact within a nine-day period, starting 48 hours before symptoms appeared are identified and advised to isolate. 12/23
Yet, to appreciate the things at play that govern transmission such as environmental factors, you need to do ‘BACKWARD tracing’. Coming back to the virus’ low K value: most people are likely to have been infected by someone who’s also infected several others. 13/23
By doing backward tracing you’re not only identifying cases and instructing them to isolate, but you’re gaining valuable intelligence as to the type of environments the spreading occurs! Something that forward T&T hasn’t given us. Thankfully Welsh T&T has started to do this 14/23
Yes, unfortunate for sectors that are dependent on indoor social environments such as retail and hospitality, but without accepting it, those sectors are going to be led down the garden path under the false pretence that their premises are “COVID secure” when they’re not. 15/23
All the while, science tells us that visors, and perspex screens aren’t effective measures to reduce airborne transmission. When you were out taking advantage of the UK government’s ‘eat out to help out’ scheme last year, both customer and proprietor were badly misinformed. 16/23
And the same can be said of educational settings. Can anyone care to explain to me how those plastic boxes are helping in any way in reducing the transmission in that school? And reducing transmission in schools is important- otherwise why were they shut for so long? 17/23
What needs to happen is acknowledgement of environmental factors, and provide support to those sectors so that we, their customers can return and enjoy what’s on offer in a safe environment as is practically possible. Ensuring adequate ventilation is one for starters! 18/23
If decisions on releasing lockdown are based solely on forward T&T data, we’ll risk repeating mistakes- increase in transmission, risking yet another wave, not properly equipping those riskier environments with the knowledge and tech to open up safely 19/23
I’m talking primarily about airborne mitigation in indoor settings, and so VENTILATION is key for these environments- how do you know your ventilation is good enough? CO2 monitors can help. I explain how here: 20/23
And if your indoor space cannot improve its ventilation, there are things that can be done- established and emerging technologies. I talk about a few of them here: Namely HEPA air filters, UV-C air purifiers etc. 21/23
So far we’ve struggled to contain the virus.
They say we need to learn to live with it- when are we going to start doing that?

If we broaden our view, accept limitations of track and trace, learn what the scientists are telling us, use what the engineers have invented.. 22/23
then those in power can make better decisions: stop cases from spiralling out of control, prevent even more deaths, get struggling industries going again and ensure the health service doesn’t just merely cope, but flourishes.
Remember- hospitals are indoor settings too.

23/END
Oh- and one extra note.
What can you as an individual do? Learn how the virus spreads. Once you know, you can then start living with it, and help others do so too.

Watch this from @trishgreenhalgh and @VickiGSP

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More from @hughes_eilir

24 Jan
Tîm Llŷn- A thread:

This weekend 3 medical practices in the Dwyfor cluster (Tŷ Doctor, Rhydbach, Treflan) got together to deliver an ambitious programme to deliver over 1000 pfizer covid-19 vaccines (a whole tray of 195 vials)

Approval was not given ‘til wednesday evening 1/16
This meant our admin staff had a mammoth task of booking over 1000 people in 2 days for the weekend.

Remember, the pfizer vaccine is tricky- once thawed, it can only be stored in a fridge for 5 days. And once a vial is open, it needs using in a matter of hours... 2/16
Our tray arrived in great anticipitation: 3/16
Read 16 tweets
13 Dec 20
Fresh Air - Awyr Iach A thread for Welsh Leaders:

For the best part of 4 months @huwwaters and I have been campaigning to raise awareness of the benefits of increasing ventilation of fresh air in indoor settings when people are in the company of others. 1/14
I haven’t hidden my frustration as to the lack of action on our authorities and leaders to take this on board and share good practice and advice with the public who really need this information. The transmission rates we’re seeing in Wales at the moment is of great concern. 2/14
It demands that we throw everything at the problem. International leaders proclaim that people are fed up, and tired of the rules, but the public need to be empowered on how they can keep themselves and others as safe as possible by keeping the risk of transmission low. 3/14
Read 17 tweets

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