Response to exclusion of aerosols in UMC Utrecht study

do 23-7-2020 16:45

Dear Mr. Bootsma,

I hope I don't bother you too much. Perhaps this is not the first e -mail you will receive as a result of your piece in the AD.

In the AD I read that you have knowledge of a valid literature list in which it is demonstrated that virustansmission is not or hardly taking place via Aerosols. You could help me and the RIVM enormously.

Omt member Andreas Voss says about the scientific evidence you mentioned: "There are very few, because since the 1980s, there are very few: all respiratory viruses have been transferred via drops and contact. That is the main feast." Aerosols may be an "add-on", but he continues: "The rest is the basis. There is no one who is researching it because we are going out: that's just the basis."

It is not necessary that such a statement is unworthy of a scientist. He defends a tunnel vision with the argument that it has been the tunnel vision for many years.

However, I feared that he was right because I could indeed not find studies that argue for the dominance of transfer via drops/contact.

Fortunately I saw your quote in the AD this morning: "There is more scientific evidence for that way of virus distribution than for aerosolent theory". So anyway!

May I therefore ask you for, for example, three (or maybe five) thorough studies that I can read myself via the internet? I mean: studies that show that the dominant virus distribution is not going through aerosols.

You are the last to whom I can turn because I catch everywhere as soon as I ask for source references. All my hope is located on you.

Sincerely,

Anton theunists.

do 23-7-2020 17:34

Dear Anton,

There is no study that provides hard evidence specifically for Corona for the contribution to transmission of large drops/aerosols (not that aerosols are the most important route, but not that large drops are the most important route). The opinion of the virological experts (I am not, I am mathematician), is primarily based on the spread of the spread of the spread of the spread of the spread of the spread of the spread of the spread of the spreads of the spreads of the spreads of the spreads of the spreads of the spreads of the spreads, and on a number of proofs and on a number of proofs and on on a number of proofs and on on a number of studies, and on a number of studies, and on a number of studies, and on a number of studies, and on a number of studies, and on a number of studies of the spread of the spread of the spread of the spread of the spread of the spread of the spread of the spreading of the spread of the spreading of the spreads of the spreads of the spreads of the spreads. Influenza.

The number of infections decreased in different countries after a one and a half meter (or 6-feet) measure was announced, because small particles are less likely to expect such a big effect as observed, this suggests that large drops play a substantial role, this does not exclude the fact that aerosolen is also important that Aerosolen is not probably that Aerosolen is not probably that Aerosolen is not probably that Aerosolen is not that aerosolen is not important. Airosols that spreading infectious diseases also typically have a larger reproduction number.

The problem is that it is very difficult to do a study that is well demonstrating the importance of the routes, you should deliberately expose healthy people to SARS-COV-2 infected patients and the distance to the patient must vary. This will not allow a medical-ethical committee because there is a substantial risk. In principle, you can measure the number of large drops and aerosols and the amount of RNA in it, but that cannot be translated directly into transmission opportunities. If an aerosol contains only 1% of the number of virus particles then a drop, with what percentage then the risk of transmission (or rises, the risk increases because an aerosol may enter the lungs). These doses-response relationships are unknown.

You would be the opinion of

Klompas M, Baker MA, Rhee C. Airborne Transmission of SARS-CoV-2: Theoretical Considerations and Available Evidence. JAMA. Published online July 13, 2020. doi:10.1001/jama.2020.12458

Being able to read once, that does not give a definitive answer, but I think the opinion of most experts is reasonably together.

yours sincerely,

Martin Bootsma

vr 24-7-2020 18:59

Best martin,

First of all, thank you for taking the trouble to answer me. Although I cannot agree with it in terms of content, it is valuable for me that you have made time for a response. It therefore feels ungrateful to respond to your helpfulness in this way because your answer raises more questions than it answers.

In any case, the content of your answer was quite shocked. Your quote in the AD was

There is more scientific evidence for virus distribution through the one and a half meter drops than for aerosolent theory.

M.C.J. Bootsma, Utrecht University

That is why UMC has excluded the aerosolent theory from the research. And that while a day before said an OMT member:

There are very few new insights, because since the 1980s it has been said: all respiratory viruses have been transferred through drops and contact. That is the main feet. Aerosols may be an "add-on" but the rest is the basis. There is no one who is investigating that because we assume: that is just the basis.

Andreas Voss, Lid Omt

Are there any evidence or not? What was the reason for excluding aerosols from your research remains dark anyway. In any case, I was curious about the sources of that "more scientific evidence".

You let us know that although you are not a virologist, it does not matter to me: a scientific view must suffice to follow logic and methodology in research reports. On the contrary, I have great faith in people who can at least count, and I trust that par excellence. (Conducting virological research is of course a different story.)

The article by Michael Klompas

You refer to an article by Michael Klompas because that would represent the opinion of virologists. The opinion of the virologists is of course known because we hear it every day on all the media, as a brainwashing propaganda machine. Unfortunately, there is no substantiation, so I asked that in the hope that a mathematician will have his affairs in order. And: you didn't seem to be part of a virologist club, because they don't know. The conscious article to which you help is, however, also a kind of opinion piece, and again of a quality that my shoes fall out.

Scientific gibberish

For example, look at the core conclusion: "The Balance of Evidence, However, Seems inconsistent with aerosol-based transmission of SARS-COV-2, particularly in well-ventilated spaces", freely translated:

"The current medical knowledge does not seem compatible with aerosolent theory, especially in well -ventilated spaces."

Freely translated into Michael Klompas

This is truly gorgeous. Ventilation is a central theme in aerosolent theory, you can't just end it because otherwise your own argument is not good. Then you can also claim that the drip theory is incorrect, especially if everyone wears mouth caps.

The piece itself is a wide -raging repetition of the same mantra. I will soon let specialists speak about that who confirm my suspicions. To my relief, there are 10 source references under the piece. That is valuable, now I might find out what drives the RIVM people.

I went through everything, at least if the abstract or the conclusion applied. That was not the case with most pieces. The majority does not apply to the posted viewpoint. And no reference supports the core rack in it Article of Michael clumps. (Kijjk again next time yourself if you recommend something)

The source references:

1. The first source reference even contradicts the conclusion of Klompas: “…coronavirus 2 (SARS-CoV-2) virus particles could be found in the ventilation systems in hospital rooms of patients with COVID-19.5 Finding virus particles in these systems is more consistent with the turbulent gas cloud hypothesis of disease transmission than the dichotomous model because it explains how viable virus particles can travel long distances from patients. Whether these data have clinical implications with respect to COVID-19 is unknown."[Other studies, incidentally, give a clearly affirmative answer to this last point of doubt.]
   “…recommendations for separations of 3 to 6 feet (1-2 m) may underestimate the distance, timescale, and persistence over which the cloud and its pathogenic payload travel, thus generating an underappreciated potential exposure range”
2. N.V.T.: Definition of "Contact Time" includes aerosol transmission. It is even stated that a mouth cap offers no sufficient protection against aerosols, which confirms its existence.
3. N.V.T.: The only connection with the transmission issue is a reference to the non-substructed conception of CDC, and we know that
4. N.V.T.: Is about transmission through "close contact", so including aerosol
5. A case (sideways) about short intense exposure to aerosols during intubation
6. N.V.T.: Case Description, shows that mouth caps protect against aerosol
7. N.V.T.: Article from 2016. Research shows that (hand) hygiene is a good idea. Wow!
8. N.V.T.: The closer a patient, the greater the chance of infection. Any protection helps
9. N.V.T.: Also about types of mouth caps in care for infectious patients
10. No idea what Klompas wants to achieve with this: “tuberculosis is almost exclusively transmitted through inhalation of aerosolized droplet nuclei into alveolar air spaces rather than through direct proximal mucous membrane contact via larger droplets. " Points to Aerosols rather than the posed position in the viewpoint.

Scientists leave no stone unturned

The comments from other scientists can be found under the article. They speak volumes. They virtually unanimously torestate the article. Have you seen that?

The 5 μm aerodynamic diameter cut-point for “droplets” is far too low. As the authors correctly note, “whether droplets or aerosols predominate in the transmission of SARS-CoV-2 has critical implications.”

John Murphy, PhD ROH CIH MACE| University of Toronto

We should disinfect indoor air with enhanced ventilation, low-dose upper-room germicidal UVC with ceiling fans, and HEPA filtration, depending upon the circumstance.

Bruce Davidson, MD, MPH| Pulmonary Medicine

Convincing the WHO of the importance of publicizing the importance of airborne transmissions is essential

Michael McAleer, PhD (Econometrics), Queen 's| Thing university, Taiwan

Very small particles may remain suspended in the air for hours, […] That such particles may spread SARS-CoV-2 is supported by calculations of saliva concentrations

Andrew Smith

The airborne transmission of SARS – CoV – 2 is a critical topic, however we disagree with the authors’ conclusion that small persistent aerosols are not involved. Particularly in large spaces where many share the same recycled air, it is dangerous to suggest that these particles are never important and can be ignored.

Joseph Brain, ScD., MA, S.M.in Hyg.| Harvard TH Chan School of Public Health

The arguments against aerosol transmission by Klompas et al. are seriously flawed.

Jose-Luis Jimenez, PhD| University of Colorado-Boulder

There are some myths perpetuated in this Viewpoint, which emanate from firmly entrenched views held by the medical profession among others.

Julian Tang, PhD, MRCP, FRCPath| Respiratory Sciences, University of Leicester, Leicester, UK

Interventions Should Be Based on Research on Bioaerosols

Mary Wilson, MD| University of California San Francisco

So far the reference that you think reflects the widely supported position of virologists.

That was the position, now the substantiation

Of course I was looking for "a number of studies into the distribution of other respiratory viruses such as Influenza" that you refer to and to which the Dutch virologists themselves always refer. In your mail you called those studies, together with indirect evidence, "the substantiation". But what sources are that then? That was my only question.

So you can't give those links either. Now I find many relevant articles myself, but they indicate a critical and often dominant role to aerosols (a selection from those sources at the bottom of the mail). So they do not help me to understand your statements and those of virologists.

We constantly point out the existence of sources that would disprove aerosolent theory. Delivering concrete references is always too much to ask. While you do screen with their own scientific expertise. Isn't that strange?

Ducking the question

Now your-yet: received an answer to the implicit assumption that COVID-19 behaves differently than other coronaviruses and other respiratory viruses. After all, you narrow my question to studies "specifically for Corona". I didn't ask about that. So that is somewhat evasive; You could even call it a fallacy.

Q: “May I ask you for, for example, three (or maybe five) thorough studies, which I can read myself via the internet and which demonstrate that the dominant virus distribution is not going through Aerosolen?

A: "There is no study that provides hard evidence specifically for Corona..."

The assumption that COVID-19 behaves differently compared to other Corona's or respiratory viruses and that we can therefore pretend that we know nothing about it, I see that nowhere is argued. Note: I am not saying that it behaves 100% identically, but you still have to start somewhere and there is enough known to assume agreements.

The one and a half meter rule highlighted

You then write: "The number of infections decreased in several countries after a one-and-a-half-meter rule was announced"

That is a particularly selective perception with which you pre -sort on the drip theory.

On Sunday, March 15, 2020, schools, restaurants and cafés were also closed in the Netherlands and all super spread events were canceled. Aerosol bees could therefore no longer take place en masse.

The latter can very well be the actual reason for the success that the "one and a half meters" is attributed. It is also theoretical/experimentally confirmed and it corresponds to observations. I have not yet encountered falsifications, only mantras. Writing to the one and a half meter rule emphasizes the blind spot of virologists.

As a falsification argument, Voss contributes that a Chinese scientist was unable to catch a living virus, 10 cm in front of the mouth of an infected patient. The same scientist will therefore take a few big breaths in the same place. Or maybe it is suddenly different.

More research on deadly viruses with a high R-number

"Also, infectious diseases spreading via airosols typically have a larger reproduction number."

That is a statement that says something about the reason to do research. In the case of diseases that was clear that they had a very high reproduction number, it was a matter (and also less difficult) to do research: where all those infections? Viral aerosols gave the answer.

As a result, diseases with a high R value were attributed the unique feature that they are spreading through aerosols. But I have not been able to find that things are different with related (and less related) respiratory viruses. You do? If so, I really appreciate a source.

The follow -up question should have been at the time: does it work with influenza and ordinary cold perhaps so? In the meantime it appears to be the case. There are studies that show that Sars, influenza and cold viruses are also distributed via aerosols. But those investigations and experiments are also ignored. Perhaps because it is only about a cold, there is little honor to be gained.

It would not surprise me if we also "flat" with better ventilation. That is particularly painful for the RIVM and I suspect that the resistance to aerosols will also come from there.

Returning to the reproduction number: that is variable and depends on the circumstances. The virus-intrinsic R0 is based on a stable "normally functioning" society. Then you should not get around carnival in the south; Then each virus suddenly gets a completely different reproduction number, and everyone is very shocked.

With hot infection fireplaces, an R value is not so useful anyway. The R is then clearly bound to certain locally limited circumstances and not intrinsic virus trait. Only with a more even spread over the country does it become a different story and gets an R-value sentence.

Doing studies is ethically very difficult ...?

"The problem is that it is very difficult to do a study that is well demonstrating the importance of the routes, to do so you should deliberately expose healthy people to SARS-COV-2 infected patients and the distance to the patient must vary."

See below, various studies in which this has already been done. In laboratory animals with Sars, in people with colds viruses and influenza. Not that all studies are equally solid and perfect, but the image is very clear and always points in the same direction.

Both from Influenza and SARS-COV-1 and SARS-COV-2 have been demonstrated that it can spread through the air. There is no reason to suspect that COVID-19 behaves differently. Staying on "we know nothing about this new virus," that is the viro glory of the century. It is also inconsistent because if that were true, how did people get the idea that COVID-19 transmission takes place via drops and contact?

Also with the cold virus, interesting experiments have been done that show that transmission through the air is the most determining distribution method. Because that disease is more innocent, experiments on people could be done with it. It also appeared: Aerosols are the dominant transporters. Furthermore, we have connected the well-known ferrets research, guinea pigs in cages via crooked pipes so that they could not immediately adhere to each other, observations of infections etc. etc.

Dose reponse at inhalation

"These dose-response relationships are not known."

A lot is known about viral load. Look at medicines that are sprayed and/or inhaled. People know the dose and people know the response, they also know what happens systemically if you make a drink or a pill. That has really been tested and measured. If you were to do that with Influenza, you might find out why patients have such a different course of the disease.

Another orientation point for imaging: the intranasal administration in medical experiments, especially when it comes to respiratory infections. That is not for nothing. Although the exact dose response may not be known, it is known that it is uncontrollably large-probably a factor that runs in the hundreds-if the virus is directly applied to vulnerable tissues such as the lungs.

Sources

As far as RIVM supporters have sometimes referred to sources, I have looked at them. Nowhere do I find substantiation for an anti-aerosol position. Often even the opposite.

Many older studies are of course only about dripping contents. That makes it especially clear where the current generation of virologists comes from. There are probably also many medical reflections that are only about letting. That was also released at some point, probably also despite urgent warnings from established doctors.

So: again no substantiation for the "one and a half meters theory".

While on the other hand there are so many sources that are waving with red flags.

[edit: I think one of the strongest is one Research from 2018 (!) Where a distinction is made between high/low airway infections, type of patients, coughing/sneezing etc. On the basis of this study, I can explain that singing together in an unnoticed space is the best greenhouse for spreading viral low-air road infections. In the second place: Horeca. I come back to that in another article.]

See, for example, the source references on the Jonathan Flux website, Covid Clinical Assessment Service. Or just check the references https://Maurice.nl (Then you don't even have to read the blogs yourself).

Als ik zelf op zoek ga kom ik alleen conclusies tegen als

SARS (2005)(!): “These data provide the first experimental confirmation of viral aerosol generation by a patient with SARS, indicating the possibility of airborne droplet transmission, which emphasizes the need for adequate respiratory protection.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7202477/

SARS (2017) “The virus might have spread via the long-range airborne route alone”,

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0181558

H5N1 (2012): “Avian A/H5N1 influenza viruses can acquire the capacity for airborne transmission between mammals without recombination in an intermediate host and therefore constitute a risk for human pandemic influenza.”

https://science.sciencemag.org/content/336/6088/1534.abstract

SARS (2018) “Increasing ventilation rate can effectively reduce the risk of long-range airborne transmission”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6072925/

etcetera etcetera. The findings tumble over each other, always with careful hints and recommendations towards WHO. They seem to think more there as civil servants than as scientists. I don't know what is going on with journalism. What the SO-Called "scientists" are doing that let their ears hang to the RIVM either.

I can't figure out why journalism does not raise all these kinds of questions. It is not that difficult to ask for sources and verify them.

An answer followed to this e -mail, as a result of which I had to write a response again. The state here.