Tue 7 Sept 2021, 10:57

WHO described SARS2 as a cough & sneeze droplet-transmitted virus

Prevention: 'wash your hands, don't touch your face'

At 12:37: #COVIDisAirborne!
'[emitted] small liquid particles...droplets to smaller aerosols'

Prevention: 'wear a mask'

Did you know? 7th Sept WHO guidance ancho...ImageImageImage
WHO anti-airborne starting point:

'The COVID-19 virus spreads primarily through droplets of saliva or discharge from the nose when an infected person coughs or sneezes' Image
WHO anti-airborne: prevention

🤦‍♂️Wash your hands regularly with soap & water, or clean them with alcohol-based hand rub.
🤔Maintain at least 1m distance between you & people coughing or sneezing [Ed: what about breath-exhaled aerosols; & why 1m?!].
🤦‍♂️Avoid touching your face. Image
7 Sept 2021, 12:37

WHO finally accepts that #COVIDisAirborne:

'The virus can spread from an infected person’s mouth or nose in small liquid particles when they cough, sneeze, speak, sing or breathe. These particles range from larger respiratory droplets to smaller aerosols.' Image
#COVIDisAirborne: prevention

✅Get vaccinated
Stay at least 1m apart from others
Wear a properly fitted mask when physical distancing is not possible or when in poorly ventilated settings.
✅Choose open, well-ventilated spaces over closed ones. Open a window if indoors. Image
Comment 🙏: there's nothing magical about physical distancing alone.

If you're indoors & the air quality is poor (inadequate fresh air supply, recirculation mechanical ventilation w/o HEPA filtration), transmission risk can be very high when sharing unfiltered, infectious air... Image
Like this: Jan 2020

2 buses, 1 pre-symptomatic case on bus 2: ALL secondary cases on bus 2

'in closed environments with air recirculation, SARS-CoV-2 is a highly transmissible pathogen.'

[No mask wearing: no known SARS2 cases in Ningbo city, China at the time] Image
'cases C5 & C10 seated in the last row were MORE THAN 5m from the index patient on the bus & neither reported direct contact nor sharing of spaces with the index patients during the event, YET THEY BOTH DEVELOPED INFECTION'

So please wear a mask indoors, regardless of distance. Image
As @WHO teams have come so far on this, hopefully it won't be long before they finally accept universally applicable physical laws underlying aerosol behaviour & change this element of their guidance on SARS2 prevention, for the benefit of all.
@mvankerkhove @kprather88 @DFisman Image

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More from @DRTomlinsonEP

10 Nov
@mancunianmedic @bmj_latest I think with 1,500 HCWs dead, over 120,000 with long covid & NHS Trusts still anchored on droplet transmission beyond AGPs, you've got a right to be angry.

You mention the pandemic stockpile lacking necessary supplies. I agree.

I hope you don't mind my 2c...
@mancunianmedic @bmj_latest In advance of PPE re-procurement, Spring 2016, the NERVTAG ‘Sub-committee on the pandemic influenza Facemasks & Respirators stockpile’ recommended that ‘fluid repellent surgical masks (FRSM) could be used for the majority of clinical care on normal wards during a pandemic...
@mancunianmedic @bmj_latest ...escalating to respirators for AGPs.’

In contrast, for MERS Coronavirus, FFP3 respirators were required for all HCWs, but as MERS was not deemed to have pandemic potential, stockpiling for this purpose was not deemed necessary.

SARS was not considered.
Read 13 tweets
9 Nov
On wearing a mask: ‘love thy neighbour’

SARS2 transmits like measles: it is breath/speech/cough exhaled, & inhaled.

‘Three children, who had arrived at the office 60 to 75 minutes after a child with measles had departed, developed measles.’

pubmed.ncbi.nlm.nih.gov/3974036/
Please bear this in mind when reading advice from @kallmemeg like this: it could just save your life & someone you’ll never, ever meet. @0bj3ctivity 💙 ImageImage
For a more evidence-based & compassionate approach to others, I suggest you follow the excellent example expressed by the captain of the Yarmouth to Lymington @wightlinkferry 👇 Image
Read 5 tweets
12 Oct
#COVIDisAirborne: For Dummies

✅ How to convince any IPC team still stuck on droplet & AGP viral transmission dogma

1. VIROLOGY LOGIC:

SARS1 was airborne, so SARS2 is airborne.

Simples!

That's why @WHO didn't want to call it SARS2, see?
1a) Need another reference?

Try this: 2013, co-authored by our very own JVT & Lisa Ritchie, Head of Infection Prevention & Control @NHSEngland

How were they ever happy letting anyone on a SARS2 ward without FFP3? 👇
2. HUMANS RELEASE AEROSOLS DURING NORMAL PHYSIOLOGICAL ACTIVITIES WHICH RESULT IN SUFFICIENT ENVIRONMENTAL AIR CONTAMINATION TO CAUSE INFECTION VIA INHALATION

Reference?

1966 ok? 👇

Read 14 tweets
12 Oct
Covid response ‘one of UK’s worst ever public health failures’

On ‘fatalism’ in the face of SARS:

‘The “impossibility” of suppressing the virus was only challenged…when it became clear the NHS could be overwhelmed.’

The NHS is overwhelmed: what now?!

theguardian.com/politics/2021/…
“This slow & gradualist [lockdown] approach was not inadvertent, nor did it reflect bureaucratic delay / disagreement between ministers & advisers. It was a deliberate policy – proposed by official scientific advisers & adopted by the governments of all of the nations of the UK”
‘The report questions why international experts were not part of the UK scientific advisory process & why measures that worked in other countries were not brought in as a precaution, as a response was hammered out.’
Read 4 tweets
10 Oct
'Myth busted'🧴: FACT CHECK

We've all learned that some prefer narrative control & advertising, to an unbiased reporting of the observable nature of reality.

W/o preconceptions re @timspector & team's approach, this arresting take from @apsmunro made me take a closer look.
/1
'there is barely any difference at all between Delta & Alpha in symptom duration, severity'

Methods: 'children were considered to have COVID-19 if proxy-reported with relevant symptoms'

Fact check🧴: This is selection bias.
It's impossible to conclude that Delta is no worse.
/2 A true myth busted: hand hygiene plays no important role in
E.g. with made up figures:

If the truth was that Covid19 symptoms occurred in 1% & 99% of kids w Alpha & Delta respectfully, the study protocol would be blind to this.

'there is barely any difference at all between Delta & Alpha in symptom duration, severity' = ADVERTISING.
/3 A true myth busted: hand hygiene plays no important role in
Read 14 tweets
10 Sep
'Proof' that 100%* of SARS-CoV-2 transmission is via the airborne [aerosol inhalation] route

@mjb302 I blame you!
@microlabdoc @hughes_eilir @Linzofm87 @huwwaters

[*to the nearest integer: obvs only ~1:10,000 fomite / contact from @CDCgov]

Pic h/t @Don_Milton

/n
1. 85% of viral RNA is in <5 micron diameter particles, which are released during normal physiological processes.

👉 Base airborne vs large droplet transmission route probability

5.6 : 1

Kudos @drkristenkc @Don_Milton & team.
2. SA of nasal mucosa with ACE2 & TMPRSS2 receptors vs total lung parenchyma.

Sinuses? I'll be generous

Say, 20 x 20cm = 0.04m*2

Lung parenchyma: ~91 v 118 m*2, F v M (mean 100)

👉 Airborne vs large droplet probability now

5.6 x 2,500 = 14,000 : 1

pubmed.ncbi.nlm.nih.gov/1626135/
Read 7 tweets

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