Since the nonsense yesterday when a public health body erroneously stated that 80% of infections diseases are spread by contact....
I promised a thread....
Lets start with the @WHO Hand hygiene guideline
@LazarusLong13 In Section 9 of WHO HH guideline the relationship of HCAI and hospital pathogens is revealed
2 assertions are made
A) Semmelweis used an antiseptic and it reduced puerperal fever.
B) Substantial evidence for hand antisepsis reducing HCAI is contained in citations 58, 179, 180

Lets have some fun... How is norovirus spread?
Ok No 1 its airborne in Scotland... exhaled and inhaled! Correction in the community in Scotland its airborne but in hospitals - its contact...

Q why would you only list "main routes" do you not need to defend against them all...

When you make a Whopper of a mistake, e.g., "airborne infections are spread by sprayed on droplets", those in charge of PH guidance should have immediately identified whether other similar errors in MoTs are present.
Consider this.
An outbreak of cryptosporidium...
1/x As @UKHSA tell us (as well as all PH agencies)... its contact
Default to contact is what is accepted for most MoTs.
Now if they are wrong - then all advice on prevention is at least incomplete. So, is there evidence of airborne?
2/x

Thoughts from yesterday's @KnowlexUK conference
Its not 2020. It is more akin to when harms from, the likes of "passive smoke", "lack of seat belts" & "asbestos" became undeniable - although not visible to all.

There are significant, persistent and undeniable harms.
1/6 So where are we now, and where do we ?need to be to negate the harms
[starter for 10]

2/6

No exaggeration here - this is a major article. Forget your CERN collider, here is a method for obtaining mechanistic evidence of far-afield airborne transmission. It was undertaken in a facility designed to study TB.
1/10 The authors state that there should be evidence of the transmission route to inform guidance.
Could not agree more. If only...

"Unambiguous demonstration of transmission routes is important."
Yes, Yes, Yes
By the way this wont come from RCTs!
2/10

After yesterday's 17:1 (one case of community acquired CVD leading to 17 others a driver diagram to reduce nosocomial transmission.

Let's start by agreeing that nosocomial transmission is unsafe.
1/8 Action 1 is to prevent transmission to patients, staff and visitors, i.e., everyone in the care environment.

2/8

I have a patient with SARS and I want to keep my other patients and staff safe.
I look up the NIPCM Scotland and find that the Main (singular) mode of transmission is both Droplet / Airborne

@P_H_S_Official this thread merits "immediate action" The Transmission Based Precautions Section tells me there are 3 modes of transmission.

It tells me what the different precautions are aiming to achieve
Of note the definitions of respiratory infections are erroneous

I honestly believe IPC as a profession will NOT survive intact if it fails to accept airborne transmission as a significant ubiquitous risk and erroneously considers hand hygiene the single most important measure to prevent infection - it is not.
See below Most important measures to prevent 🫁 non VAP pneumonia - patient positioning, mobility, oral hygiene

Great. Can we start with the pandemic.
The mental models for transmission have been done by world experts in aerosols (not IPC).

Here is of @trishgreenhalgh 's evidence on the virus being airborne.

https://twitter.com/hugo__sax/status/1726162099544453538

Here is one by Marr & Tang
Their comment on the <5 >5 IPC paradigm is it defies physics.
Its from 2021 pubmed.ncbi.nlm.nih.gov/34415335/

They have withdrawn masks in Scotland's Healthcare system and referred 'concerned staff' to complete a risk assessment. healthyworkinglives.scot/resources/form…

Lets fill out their risk assessment... I am (for the form) a ward manager
Describe the task:

Any patient-to-HCW, HCW-to-HCW, patient-to-patient, or visitor-to-patient or HCW interaction in any close space, e.g. conversation or stethoscope range

or when ventilation poor just being on the ward.

Considering how the 'collective we' made Mode of Transmission Errors - some possibilities

a) we turned doubt in to certainty, the use of qualifiers in original work were turned into fact, eg.

'droplets have traditionally been defined as ...'
became
'droplets are defined as ' a) More doubt to certainty
Dr X et al showed that viruses can get in to the eyes, nose and mouth

was translated to

Dr X et al showed that all droplets get in via the eyes nose and mouth

7 slides showing that neither CDC nor WHO presented evidence for the existence of droplet transmission
You may have seen this from the WHO most pandemic refs refer to it - note lack of evidence (its not in 5), and in the def or aerosols it says 'its not yet clear' This is from the CDC which cites references showing 'outbreak evidence', 'experimental evidence' and 'aerosol dynamics'....
Only relevant outbreak reference is 101 - lets get it...

In this preprint I believe there is a call for RPE - which is excellent
medrxiv.org/content/10.110…
The authors states...
"Appropriate PPE and mask use are essential as SARS-CoV-2 is frequently detectable in the air surrounding positive patients."

Importantly.... (see next tweet)

https://twitter.com/DRTomlinsonEP/status/1580468469371662337

Specifically stating:
"We believe our data supports the use of FFP2/3 medical masks for HCWs caring for COVID-19 patients, particularly for those with prolonged contact in line with HSE guidelines 15"

However I believe they may have made an error....

The IPC world entered the pandemic with an erroneous paradigm for the transmission of respiratory infections.

What if this was not the only erroneous paradigm? What if we have to go back and review all routes of transmission? Here is the latest MRSA guideline 2021 - the focus is on prevention of transmission - good.
'MRSA is easily spread by multiple routes' - unhelpful which ones?

Monkeypox - NON EXPERT HERE
Just going to highlight some variations in transmission definitions.
NB when we get the definitions wrong we get the precautions wrong (See COVID for details).

Note - none of these definitions come with references.

Let's start with the @WHO The @WHO as already stated describes inhalation of the virus as FOMITE Transmission.
But if you can inhale the virus from bed linen why can't you inhale from exhaled breath when its in resp secretions?
Specifies skin-to-skin - does this mean the virus invades intact skin ?

W. Edwrds Deming - The Quality Improvement guy set down 14 points for Management which are still relevant today.
I am going to adapt them for COVID management.
This is my first attempt - improve them where you think
deming.org/explore/fourte… 1. Create a constancy of purpose toward improvement of product and service, with the aims
to achieve zero COVID transmission, &
to reduce both the health impact and the financial impact on people, businesses by having people sufficient fit at their work.

A useful paper and its sister paper may prove yet more useful. Curran A. COVID-19 outbreak investigation to understand transmission (in progress)

Both lead authors are with the @H_S_E

The problem is that the NHS will have to wait >3years into a pandemic before....

https://twitter.com/PROTECT_NCS/status/1549346620914995200

... @H_S_E recognises from its own data that SARS-CoV-2 is airborne

People are admitted to hospitals with covid (& acquire it there) where inadequate droplet precautions are in place

What is the @H_S_E going to do when they produce their own evidence that covid is airborne?

As the pandemic shows no signs of disappearing (despite the politicians efforts at pretending its not here any more), its time to look again at national and international public health pandemic web pages - specifically on transmission & ventilation The WHO
Improved. Includes short and long range aerosol transmission.
Includes new guidance doc on ventilation
Evidence of new 'living guidance' in production
But...
Unsure why Respirator recommendation is 'conditional'
Unsure why AGPs strong recommendation - refs needed here.

I offer some reflections:
I'd really rather we waited until the epi curve was flat for a period of time without VOC circulating before 'post pandemic' terminology was used by the IPC community. We're not not post pandemic, it's mid pandemic at best.

https://twitter.com/jhieditor/status/1543897595323551744

The most fundamental research needed is retrospective. How did we do? What did we get wrong? How could we have done better? A full High Reliability Assessment. The mode of transmission was and is wrong. The precautions were & are wrong and the obsession with AGP is inexplicable

I have been undertaking a review of SAGE minutes and associated papers to find out why HCWs who care for people with SARS-CoV-2 are not afforded FFP3 protection. I am up to June 2020 between Minute 40 and 41 & this is a critical paper. assets.publishing.service.gov.uk/government/upl… This EMG report makes this unreferenced & incorrect assumption:
"Transmission of SARS-CoV-2 is most strongly associated with close and prolonged contact suggesting that close-range direct person-to-person (droplets) and indirect contact are the most important routes. "

DELVE Report to SAGE: assets.publishing.service.gov.uk/government/upl… April 21st 2020
Droplets from infected individuals are a major mode of transmission (WHO)
Ergo surgical masks are adequate protection in most settings (PHE) link not working.
More... "Droplets come from talking and breathing as well as sneezing and coughing. " Ref to a letter nejm.org/doi/pdf/10.105…
Which says: speech generates oral fluid droplets that vary widely in size - 20 - 500um
Small droplets can dehydrate & become droplet nuclei – behave like aerosols