Smoking COVID

Many common diseases are spread through the air by tiny particles called aerosols; these include influenza, chicken pox, mumps, measles, pertussis, tuberculosis, diphtheria, rhinovirus and the coronaviruses (Ref). 

The preponderance of scientific and epidemiologic evidence supports that SARS-CoV-2, is transmitted via infectious airborne aerosol particles, both near and at a distance from the source, especially in shared indoor spaces. (Ref, Ref, Ref, Ref, Ref, Ref, Ref, Ref) 

Science Direct, respected journal of peer reviewed scientific literature, states in its article – ‘Airborne transmission of SARS-CoV-2: The world should face the reality’:

“Hand washing and maintaining social distance are the main measures recommended by the World Health Organization (WHO) to avoid contracting COVID-19. Unfortunately, these measures do not prevent infection by inhalation of small droplets exhaled by an infected person that can travel distances of meters or tens of meters in the air and carry their viral content. Science explains the mechanisms of such transport and there is evidence that this is a significant route of infection in indoor environments. Despite this, no countries or authorities consider airborne spread of COVID-19 in their regulations to prevent infections transmission indoors. It is therefore extremely important, that the national authorities acknowledge the reality that the virus spreads through air" (Ref)

This virus’s predecessor, SARS-CoV-1, was also spread via airborne transmission. This was reported in several studies which retrospectively explained the pathway of transmission.  These studies concluded that airborne aerosol transmission was the main route of infection in the indoor cases examined. 

Early studies of airborne transmissions were hampered by the fact that the investigators did not have the technology to detect small particles less than 5 μm near an infectious person.  Therefore, they assumed that it was the exposure of the face, eyes and nose to large particles over 5 μm in size, or “droplets”, that transmitted the respiratory condition to a person near the host (Ref).  This became known as “droplet infection”, and 5 μm or greater became established as the size of large particles and led to the traditional belief that such particles could, in theory, be trapped by something like a face mask.

The early researchers concluded that since only large particles were detected near an infectious person any small particles would be transmitted via air currents, dispersed over long distances, remain infective over time and might be inhaled by persons who never had any close contact with the host (Ref).  This became known as “airborne transmission” against which a face mask would be of little use due to the microscopic size of the airborne particles.

Through the use of highly sensitive instruments it is now appreciated that the aerosols generated and transmitted from the respiratory tract due to breathing, range in size and are indeed microscopic at less than 5 μm (Ref). 

An aerosol is an "aero-solution", and can be defined as a suspension of fine solid particles or liquid droplets in air or another gas.  Examples of aerosols include fog, mist, dust, forest exudates, tobacco smoke, vape smoke and exhaled human breath.  

As both smoke and viruses (Ref) travel through the air as aerosols of comparable size, an understanding of the behaviour of smoke might help in our understanding of how airborne viruses like coronavirus are spread, therefore assisting us in knowing what measures might work and what measures won’t.

The aerosols of smoke can contain both liquid and solid particles, which can usually be smelt quite easily, providing a useful perspective of how far and at what rate aerosols can travel through the air.

It is known that viruses are exhaled in our breath as tiny aerosolized particles of less than 5μm and can remain in the air for at least 3 hours and travel long distances. (Ref, Ref) 

It has been demonstrated that, through normal breathing, over 80% of infected and symptomatic individuals produce sub-5μm aerosol particles which carry viral RNA. (Ref)

Before going on, it is necessary to discuss sizes and scales for comparative purposes.  It's not very often that people need to talk about something as small as a virus.

Viruses are so small they can only be seen with an electron microscope, and have to be measured in millionths of a metre - micrometres (μm). There are 1000 μm in a single millimetre.

The following diagram provides us with some graphical context.  A typical coronavirus is the smallest little red dot on the bottom left.  SARS-CoV-2, the coronavirus which can lead to the diseased state known as COVID-19, is reported to measure only 0.125 μm.  Which means you could stand 8,000 of these viruses side-by-side within a single millimetre.

The SARS-CoV-2 particle is 56 times smaller than a red blood cell, which is one of the smallest cells in the human body, at only 7μm.  A single red blood cell is invisible to the naked eye. 

For scale, the diagram below shows a single human hair as a benchmark on the upper end of the size range.  Look at how thin a human hair is, yet it is 1,200 times wider than a SARS-CoV-2 virus.

To the right of the coronavirus in the diagram we can see a smoke particle at 0.4 to 0.7 micrometres, which is 3-6 times bigger than a SARS-CoV-2 virus particle.
 Tobacco smoke as it comes from a cigarette is an extremely concentrated aerosol with a distribution of sizes larger than SARS-CoV-2, ranging from 0.1 to 1.0 μm.  Most people are well aware of the distances which tobacco smoke can travel because its easy to smell, which gives some perspective of the ability of aerosols to travel in and permeate the air.

View the full-size version of this infographic.

When breathing, small airways close and the reopening process produces minute aerosol particles ranging in diameter from only 0.7 to 1.0 μm (Ref).

 

These tiny aerosols we breath out cannot normally be seen.  However, during the winter months, when the air is crisp and cold, the warm moist breath and its copious aerosols are clearly visible.

 

The moist bioaerosols in the breath can also be observed at any other time of year by breathing onto a cold piece of glass.  The wet opaque surface layer that you breathe onto the glass is scientifically termed as ‘exhaled breath condensate’. It has been found to contain exhaled water, dust, cell particles, proteins, DNA, bacteria and viruses.

The same moist aerosols in someone’s breath can be seen as they follow the path of least resistance up and around the sides of a mask and onto a person’s glasses, annoyingly causing them to fog up.

Millions of aerosol particles can be exhaled with every breath. Once released, they loyally obey the laws of physics, taking the quickest and least obstructive path into a lower pressure space. The attempt to contain, filter or prevent the diffusion of millions of microscopic aerosols from an exhaled breath, using only a loose-fitting piece of cloth in front of one's nose and mouth, is like trying to hold onto fog with your hands.

 
The World Health Organisation defines droplets as being equal to or greater than 5-10 μm in diameter, and aerosols as being less than 5 μm. However, this arbitrary 5-10 µm threshold commonly used to dichotomise airborne and droplet transmission has been criticised as it has never been supported theoretically or experimentally.

   

It may be argued that by stopping some of the largest droplets, the infectivity of an individual may be reduced.  This is true to a degree but also tantamount to saying that, if on the battle field you were being fired upon by the occasional cannon ball, in amongst the sweeping machine gun fire of thousands of bullets, maybe stopping some of the cannon balls might prevent the bullets from harming you, when in fact it would make more sense to be more aware of the real dangers of both, and stay out of range of both.  "There is no evidence that some pathogens are carried only in large droplets." (Ref) 

The notion that some protection must be better than none is tantamount to wearing a woolly hat instead of a proper safety-certified helmet on a motorcycle. Only a very low level of 'minimal infective dose' (MID) is required to cause an infection, with a handful of airborne virus particles being enough to meet MID for a respiratory virus infection such as SARS. (Ref)

Attempting to temporarily trap some larger droplets in a face-covering, which will continue to evaporate into bioaerosols anyway, sounds good but makes no sense. We know from history that airborne viruses cannot be contained. It is the strength and health of the population which determines the outcome, no political interventions.

"The 2-metre social distancing rule assumes that the dominant routes of transmission of SARS-CoV-2 are via respiratory large droplets falling on others or surfaces.

A one-size-fits-all 2-metre social distancing rule is not consistent with the underlying science of exhalations and indoor air. Such rules are based on an over-simplistic picture of viral transfer, which assume a clear dichotomy between large droplets and small airborne droplets emitted in isolation without accounting for the exhaled air. The reality involves a continuum of droplet sizes and an important role of the exhaled air that carries them."   - Oxford University Centre of Evidence Based Medicine

Source - Airborne transmission of SARS-CoV-2: The world should face the reality

A belief in the safety of wearing a mask to protect us from the dangers of large droplets, whilst ignoring the danger posed by aerosols, is a dangerous false belief system, as almost all masks in popular use are unable to filter out the microscopic 'bioaerosol bullets' (Ref). 

In the following video, Doctors talk about airborne disease transmission and physically demonstrate how a wide variety of masks and face-coverings are unable to prevent virus bioaerosol transmission.  The masks may temporarily catch the 'cannon balls' but not the thousands of 'bullets'. A vape is used for demonstration purposes as it produces aerosols which are very easy to see. The aerosol particles emitted from a vape measure 3.4μm, which is 27 times larger than the SARS-CoV-2 virus. But if the virus is contained within the normal water-based aerosols of our breath, measuring 0.3 to 3μm, the comparison is fair and reasonable. As you will see, the vape aerosols go through and around all the masks and face-coverings with ease. 

Typically, the popular counter argument against masks is that surgeons wear them, and as high-ranking professionals, they must know better.  This is of course based upon the fallacious assumption that surgeons wear masks in surgery to prevent virus transmission. This is not true.  Please read this extensive document produced by the Association of American Physicians and Surgeons for a detailed analysis of the question of masks as protection against virus transmission.

A good understanding of aerosol physics, airflow, and dilution is helpful to interpret the behaviour of potentially infectious aerosols in complex real-world situations.  Research in aerobiology, physics, and computational fluid dynamics has advanced the understanding of aerosol generation and the carriage and fate of respiratory particles. 

According to aerosol scientist, Dr. Jose-Luis Jimenez, the theoretical limitation of aerosols to less than 5 μm is not scientifically supported.  Experiments demonstrate that significantly larger particles (~50 μm ) can be exhaled and carried in the breath, remaining airborne and floating through the air.   Smaller aerosol particles (≤5 μm), are light enough to remain suspended in the air for hours, analogous to pollen, which ranges in size from 15 to 200 μm.  He states that particles of 5 μm or smaller in size can remain airborne indefinitely under most indoor conditions (Ref).

One infected person will produce about 2.5 million particles per 8-hour period just from breathing, which is more than capable of saturating a normal domestic or office internal air space. These aerosols containing infectious virus can travel considerably farther than 2 metres and accumulate in poorly ventilated indoor air. (Ref)   

"There’s no reason to be walking around with a mask. When you’re in the middle of an outbreak, wearing a mask might make people feel a little bit better and it might even block a droplet, but it’s not providing the perfect protection that people think that it is. And, often, there are unintended consequences — people keep fiddling with the mask and they keep touching their face" - Dr. Anthony Fauci, (USA Coronavirus Task Force), March 2020.

A 2008 UK Government Health & Safety Executive (HSE) report - “Evaluating the protection afforded by surgical masks against influenza bioaerosols”- clearly stated:

“In principle, surgical masks provide adequate protection against large droplets, splashes and contact transmission. There is a common misperception that they will provide protection against aerosols”… “they should not be used in situations where close exposure to infectious aerosols is likely.” (Ref)

The fact that basic and surgical masks only reduce large droplets and provide no protection from bioaerosols is confirmed by multiple sources, including the Association of American Physicians and Surgeons, which states:

“[A]any respiratory protection respirator or mask must provide a high level of filtration and fit to be highly effective in preventing the transmission of SARS-CoV-2. [Ability to block Mycobacterium tuberculosis (3μm)]” (Ref)

Professor Beda Stadler, emeritus Professor of Immunology from the Medical Faculty of the University of Bern, states that the masks being worn by the public “gives a false sense of security and its just ridiculous”…”People have no idea how small a virus is, it is like expecting a football goal to stop a ping-pong ball”…”it has become a belief system, like a religion”.  

Another factor which appears to be missed, is the fact that airborne viruses can and will infect a person via the air which makes contact with the eyes. A typical grain of pollen measures 15μm, which is 120 times larger than the coronavirus [Ref].  As any hay fever sufferer will attest, pollen floats invisibly through the air and gets into the eyes, lungs and sinuses; as will SARS-CoV-2.

Only a sealed breathing system, with an independent clean air supply and a mask which seals to the face and incorporates the eyes, is going to properly protect a person from microscopic viruses expelled in the tiny aerosols generated by the breath of an infected individual.  A face-covering and standard surgical mask might actually endanger a person by creating a false sense of security.

Normal masks and face-coverings don't control virus infection, they control you.

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For a complete dissection and explanation of aerosols and airborne particles, please see Understanding Particle Size and Aerosol-based Transmission by Steve Probst.