Inhalation of hot humid air at high temperature: a preventive and / or curative means of combating the coronavirus? And, moreover, quarantine, although necessary, can be counterproductive unless the measure of wearing the mask for everyone, all the time and everywhere is not applied radically.



March 8, 2020

By Pierre-Jacques Raybaud - Doctor, general practitioner, post-graduate in immunology, research in human biology.  -  ORIGINAL ARTICLE.


The aims of this article are, in view of the urgency, firstly to draw the attention of the general public to a simple preventive, and indeed perhaps therapeutic, action which makes sense from a scientific point of view, and secondly to draw the attention of healthcare experts to this point of view.

We believe that doing so is a matter of important public interest.

First, some ancient history...

According to the Ebers Papyrus, in ancient Egypt, people put palm wine into their nostrils to treat coryza. In Europe as well as in China, Japan and other continents, inhalation over a bowl, with a towel over the head, using various plants, was a common measure to clear nasal obstruction. Let us note, however, that none of these plants or other essential oils actually have a virucidal effect.

Of concern to all of us now is this distressing coronavirus, the SARS-CoV-2, called COVID-19 by the World Health Organization (WHO).

The coronavirus…

Several viruses are transmitted through the respiratory tract: influenza virus (the well-known “flu”), the rhinovirus, the measles virus (for which we cannot over-emphasis the importance of vaccination, entirely safe and in any case, mandatory, at least in France), the syncytial virus, the adenovirus, the coronavirus and many others.

Some viruses, including the coronavirus, also spread through the fecal-oral route. Of note is that while the flu generally kills thousands annually, this year, for France, since the beginning of the coronavirus epidemic, the flu, as of writing (week 9) has “only" led to 744 hospitalized patients, of whom 72 have died to date.  Of note is that this flu victim tally does not give any information as to the potential role played by the coronavirus in that tally. This is curious. In passing, we remind readers of the obvious interest of getting those “flu shots”. Of the serious patient cases taken into intensive care, 25% were vaccinated and 75% were not, which points to a vaccine efficacy of around 75%, as shown by figures that are more or less identical in other countries. Many of the influenza-like illnesses (ILI) among the vaccinated serious cases were therefore not actually influenza, despite assertions to this effect by the first responders (the “SAMU”) and thus, these people were too often not even tested for the coronavirus. The Influenza Epidemiology Bulletin published by Santé France has reported a 10% mortality rate amongst patients admitted to intensive care for influenza. But we are now leaving peak influenza, and yet, in our doctor’s office, we observe an increase in ILI (typical cases plus attenuated forms, not counted in the French GPs' Sentinelles Network, to which should be added people who didn’t bother to go see their doctor because affected only by very minor, yet contagious, ailments such as sore throat, blocked or runny nose without fever, etc.).

The coronavirus has been known for a long time. Like other viruses, it mutates, changes and adapts by self-replications within the living organisms it attacks. There are now two strains, one of which is aggressive. Over the weeks and months to come, it could mutate into something less aggressive. Of course, it could also mutate into something even more aggressive.

In Hong Kong, from November 2002 to July 2003, SARS-CoV contaminated 8000 people and killed 774.  In the Middle East (Qatar, Saudi Arabia...), between 2012 and 2013, MERS-CoV contaminated 1714 people with 618 deaths.

Regarding the mortality rate of 2.0% to 3.4% of the current SARS-CoV-2, depending on the reporting source, it should be noted that this is calculated with respect to detected cases.  Now, obviously, a great many people are infected but have not been detected. Thus, the actual mortality rate is necessarily much lower. An extrapolation of contaminated cases to attain meaningful, because sufficiently broad, data is difficult without an increase in systematic tests.

We recommend the systematic screening of test panels, selected at random, with and/or without clinical signs. This would give us a better understanding of the actual rate of spread of the virus. This approach is already underway in South Korea.

For sure however, we can say that the coronavirus is already ubiquitous.

Several animals are contaminated and can act as potential reservoirs: civets, cats, camels, pangolins, bats and many others. The coronavirus is exhaled, but it is also excreted in faeces (2) and urine. The respiratory tract plays a major role and has already been shown to be important for SARS (22). Specifically, SARS is not caught by eating cooked meat (since cooking destroys the virus), but mainly by breathing the exhaled particles of live animals and dust from their contaminated droppings. It is essential that suitable veterinary legislation be promulgated.

In order to understand the following sections, it is fitting that we first explain the concept of viral load. The viral load is the total mass of virus in a commonly infested organism. Viral load is used and measured in many viral diseases (AIDS, for example). The more viral particles a patient repeatedly receives, the greater the risk of triggering an illness. Viral load is also one factor, amongst others, in determining the severity of the course of an illness. It is therefore essential to reduce the viral load; after all, staying one minute in a confined space or area with a contaminated person will not have the same impact as staying there for hours or days.

… is transmitted via the respiratory and fecal-oral routes.

The German bacteriologist Carl Flügge, as early as the end of the 19th century, understood that certain infectious agents used expired droplets and aerosols to transmit diseases.

And indeed, the mode of respiratory transmission is through secretions (nasal mucus, sputum), large droplets (10 to 100 microns), exhaled by a contaminated person (sneezing, coughing) and aerosols, fine droplets (5 to 10 microns) such as can be seen condensing on a cold window pane on exhaling up very close to the pane. The speed of exhalation and interpersonal distance are crucial. Physical activity, by accelerating the respiratory flow would be expected to increase the risk of transmission. A distance of one meter can be considered as offering partial protection (4, 5). But a cough can project particles at 8 meters/second, and contaminate even further away. Worse again, aerosols of 5 microns or less can remain airborne for 1 to 18 hours.

In addition, these considerations do not take into account a possible draft which then makes social distancing hypothetical. We admit that beyond several tens of meters a cloud of aerosols is theoretically diluted. Unfortunately, a downside must be clarified here. In fact, you can smell a burning smell almost a kilometer away without receiving smoke. It depends on the air flow and its direction. You need combustion gases and ultra-fine particles less than 5 microns like aerosols. The longer the distance, the less likely you are to receive a lot. However, on a forest fire, sometimes very far away, depending on the direction and the whirlwinds of the wind, you can receive a mass of particles and smoke greater than to the point of coughing. This explains why, even if it is rarer, it is possible to be contaminated more than a kilometer away.

Two experiments have already proven this with viruses: - ducks contaminated by bird thrush exhaled aerosols and contaminated a group of healthy ducks several kilometers away. - pigs parked and sick with swine flu contaminated a group without parking more than 100m away.

That is to say, the relativity of this social distance. Inside an establishment, air currents make it possible to reduce a suspended viral load but, also, redistribute the virus in all rooms

Which is why it’s important to properly air premises.

However, if a person is infected, then the ventilation must be controlled by filtering or some other technique, so as to prevent the virus from spreading outside.

The virus, once deposited on the oro-pharyngeal mucosa, will incubate and take around 10-12h to penetrate a cell and then will replicate itself, initially, in the two millimeters thick respiratory epithelium and then spreads throughout the body. When exhaled, the coronavirus dies at room temperature in 3 hours on a dry surface, but it can survive for up to 10 days on a wet surface.

These aerosols of more than 5 microns will be deposited in and around the ENT sphere: this category accounts for most use cases and are mainly deposited by impaction. Aerosols between 2 and 5 microns reach the bronchial tubes by impaction-sedimentation. Only aerosols under 2 microns will descend by diffusion into the pulmonary alveoli (24). We also know that the mucociliary escalator pushes particles, not yet seeded, upwards into the ENT sphere. It is assumed that 99% of inhaled particles are eliminated within 48 hours, with however the remaining 1% penetrating the epithelium and once inside, growing. It should be noted that these viruses surrounded by mucus and phlegm are even more protected outside.

Modern rapid detection techniques using PCR (polymerase chain reaction) allow the virus to be detected in blood, throat and nose, urine or faeces. At the beginning of the epidemic, the French Ministry of Health chose to entrust responsibility for testing solely to the first responders, doing so according to very strict criteria, one of which pertained to the likelihood of the suspected case having been in contact with confirmed cases. These criteria are now considered too restrictive. Such an approach is normal and cost-effective at the beginning of an unknown epidemic with an unknown outcome, and has a clear goal: avoid paranoia. However, where a virus is spreading very quickly, rapid in vitro replication work done by the Institut Pasteur (20) shows that this approach leads to a significant underestimation of the scale of the epidemic. Systematic random testing in Wuhan, China, suggests a rate of 1% to 5% among people without any obvious illnesses, i.e., about 2 to 3 people out of 50 are contaminated without any signs. This shows the extreme contagiousness and very high spread of the virus.

This underestimation is all the more pronounced in that there are many people with very few symptoms or even none at all, or perhaps with just a simple cold without fever: people are nevertheless contagious for two days, or even longer, before the manifestation of the disease (there is still some uncertainty on this point). As soon as we start confining persons, we observe even more cases because, in this situation, we multiply the tests. Moreover, by remaining confined, families easily infect each other.

In reality, the coronavirus has exploded.

On February 21, a team of Chinese radiologists published a map of confirmed cases in China: the whole country is contaminated (Coronavirus Disease 2019, February 21, 2020, ZU ZY, Jinling Hospital, Nanjing).

While the test does have a cost, the pandemic, already underway, warrants that all health care professionals should be able to treat it, and not just first responders or hospitals. Doing so would obviously lead to many more cases being detected in France. This would have the combined beneficial effects of reassuring the general public whilst optimizing the allocation of healthcare resources. The first responders are already overwhelmed, and their workload should be shared by other healthcare professionals, failing which hospitals won’t be able to cope. At the moment, you can’t get yourself tested unless you’ve been in contact with a confirmed case.

In these current exceptional circumstances, it should be possible to run tests for all influenza-like illnesses (ILI).

Widespread containment and border closures will serve no purpose if more drastic hygiene measures are not taken, measures which, in any case, the virus will have already side-stepped. Moreover, the perverse and counterproductive effects of the economic slowdown will in turn have a deleterious impact on the fight against COVID-19: lower stocks (masks, antiseptics and medical drugs), hospitals stretched to breaking point, reduced public transport services, work strikes, personnel refusing to work, factory workers staying at home, teachers likewise, parents whose children can no longer go to school, caregivers and many other professions absent, just to name a few.

Clinical signs of SARS-CoV-2 or COVID-19

According to the first Chinese studies (12 and 13) on 41 hospitalized patients, the common symptoms at onset of illness were (not necessarily high) fever (98%), cough (76%), myalgia or fatigue (44%); mucus (28%), headaches (8%), dyspnoea (55%) eight days from onset of the illness, bacterial superinfections (10%) and most strikingly severe acute respiratory distress syndrome (29%) and deceases (13%).

The other study concerns a family (13), all infected with the virus, except for a 7-year-old child who wore a basic surgical mask all the way from Shenzhen to Wuhan. Even though highly exposed, she was not infected. Two had a runny nose and a slight sore throat without fever.  Thus, and notwithstanding the uncertainty as to exact numbers, it seems reasonable to assume that there are many cases with few or no symptoms (between 10% to 50% in the opinion of various experts).

By contrast, the February 29 study, conducted by the Chinese team in Jiangsu on 80 people, shows that only 3.7% of cases were severe, with no deaths, and the rest had only moderate symptoms.

 The COVID-19 virus requires deploying a broad arsenal of measures to counter its advancement.

Measures to counter COVID-19 apart from medical treatment

The recommendations made to health professionals are more or less the same as those recommended for SARS-CoV virus of 2003: minimize contact with patients in waiting rooms, minimize patient waiting times, get people manifesting warning signs to wear a mask, make sure the medical practitioner also wears a mask, disinfect surfaces, avoid shaking hands with others, wash one’s hands frequently, and wear eye glasses.

One remark is worth noting. How can we expect all bearers of influenza-like illnesses to stay at home? The first responders will certainly not be able to cope with the deluge of phone calls requesting their intervention. Likewise, we general practitioners can only do so many house calls in a day. By contrast, a strict observance of the rules set out here could help doctors cope with a significant increase in the number of patients seen. And we need to be realistic.

To these recommendations, we would add: disinfect the stethoscope and use disposable tissue when measuring blood pressure. The blood pressure monitor goes from patient to patient. As the only instrument never to be disinfected in doctor's offices and hospitals, it will touch the skin of thousands of patients before giving up the ghost in 5-8 years! And then, of course, we have computer keyboards and mobile phones, both veritable hotbeds of viruses and bacteria according to hygienists.

Whenever a prescription is given to a patient with ILI symptoms who wore a mask during the consultation, the patient should wear that mask on subsequently entering the pharmacy, another cradle for the spreading of viruses. These practices should be implemented and recommended.

In spite of official declarations to the contrary, it should be compulsory for all to systematically wear a mask in crowded or confined areas (metro, train, taxi, car, bus, airport, railway station, large gatherings). This practice would help slow down the spread of the virus and limit the very worrying economic fallout.

It is our opinion that, at this stage in the course of the COVID-19 pandemic, there is no longer any point in pursuing containment, which, in the absence of stricter hygiene measures, will actually increase the number of cases (China, Italy, Korea, outbreaks in France...), and likewise the recommendation concerning restrooms. We already made this point in our article of March 2, and this was confirmed by a recent study of March 4 published in JAMA (27).  We believe that that most important thing is to put up a respiratory barrier, to live a normal life within a functional economy, but where everyone is required to wear a mask (general public, healthcare professionals, police, taxi drivers, civil servants, etc.). We are convinced that doing so would stop the epidemic for sure in less than six weeks. As regards the masks themselves, it must be noted that French factories are currently running at full capacity. But this is not enough.

The State should lay on sufficient resources to co-finance the construction of additional plants as soon as possible. The current official doctrine that is “No Symptoms – No Mask" does not withstand scrutiny and must radically change: Everyone should be mandated by law to wear a surgical mask under all circumstances.

This massive mask response is only beginning; for example, Japan is currently having 600 million masks made, just for the month of March. Here, we keenly note that the virus has spread slower in Japan than in France; to wit, although densely populated (126 million) with highly concentrated urban areas, Japan has, to date, recorded “only” 480 cases for 7 deaths compared with France with 949 cases for 16 deaths with a population of 62 million. We attribute this to the well entrenched and commonplace practice of wearing masks in Japan.

If China sneezes, the West catches a cold. And whilst it is reassuring to note that measures of international cooperation are gradually being rolled out, much remains to be done.

We hear: “Sneeze into your elbow". Please note that this advice is meaningless if you don't spray your elbow crease with antiseptic immediately afterwards, as you would for your hands


Although by no means perfect, the classic surgical mask does have a certain effectiveness. In spite of leak rates of between 10% to 20%, it is striking that, in the Chinese study (13), the child wearing a mask was not found to be infected even though she was in close proximity with people who were, and moreover, for an extended period. Thus, perhaps not perfect but clearly better than nothing. Of note is that the classic surgical mask no longer performs its functions correctly after 4 hours of use.

A simple way to reuse a mask

Drying a used surgical mask with a hair dryer positioned at a distance of 5 cm with High Heat selected (i.e., temperature of 120°C to 150°C) can destroy almost all viruses and bacteria in just one minute. The heat must also be applied to both sides of the mask and to the straps. An excellent 2014 doctoral thesis, entitled “Inactivation virale par méthodes physiques” (Viral inactivation by physical methods) by Swan Firquet, directed by Prof. Didier Hober virologist in Lille (21), discloses that H1N1, which is more resistant than a feline coronavirus, is destroyed in 1 second at 100°C.  According to Duizer et al. (2004), the feline coronavirus is reduced by 1000 in humid heat at 71.3°C in 1 minute, and is totally destroyed in 6 minutes.

Therefore, as long as the texture of the mask is not altered, it can be reused by the same person after blow-drying, at least in the case of a shortage. Masks should be blow-dried at high heat every 4 hours, and can be re-used for a maximum period of one week.

Face masks apart, in the event of a shortage, it is important not to overlook the fact that a thick absorbent paper folded in four or a thick scarf (rather in silk or cashmere double layer) placed properly on the face offer a filtration efficiency and leak rate that are only slightly lower than those of a surgical mask.

This process also sterilizes clothing. Warning, never turn it on in cold air, warm air must be applied before sweeping the heat beam close enough on the mask, hair or clothing.

(addition of recent data from April 2020: The Covid would be destroyed in 4 minutes at 63 °, which corroborates the previous data).

I proposed the manufacture of a quick, seamless artisanal mask, with few means, scientifically tested at the filtration and leakage rate, in absorbent paper 4 thick layers intended for poor people and / or countries with little means, intended to be recovered by NGOs for example, in a mask shortage phase. See the video below.

However, and depending on the quality of the surgical masks, the filtration rate can range from 65 to barely 75-80% with a very bad leakage rate for some 25-30%.

For information, an FFP1 filters at 80% and leaks at 22%. (after studying under a microscope a sheet of thick absorbent paper folded in four under a simple mask, reduces the filtration rate to that of an FFP2 towards 95%)

FFP2 and FFP3 masks are better.

FFP2 and FFP3 comply with the European standard, E149. The FFP3 has a filtration efficiency of 99.95% and a leak rate of 2% while the FFP2 has a filtration efficiency of 94% and a leak rate of 8%. FFP3 is clearly the better product, capable of blocking solid particles down to 0.6 micron and liquid particles down to 0.9 micron. It is preferable to have an exhalation valve, otherwise the humidity quickly becomes unbearable. These masks can also be blow-dried (120°C applied for 1 minute) and re-used for a maximum period of one week.

The personal making of a mask.

The Grenoble University Hospital offered a tutorial close to an FFP2. However, it was forgotten to add an aluminum rod on the nose and a foam bar inside to reduce leaks. the best tutorial seems to be that of this textile engineer. It is advisable to download the tutorial and explanations. It takes 40 to 60 minutes without being experienced to achieve it. A presentation will be made on simple means on Youtube.


Frequent hand washing is very important as is regular disinfection with an alcohol-based hand sanitizer. And of course, you should not be touching your face with your own fingers.

You should also regularly disinfect phones, keys, coins, office materials and indeed any objects frequently used by others.

The deficit of hydro-alcoholic gel or antiseptic is easy to solve.

  Take a 500cc sprayer, fill it with water and add a quarter of bleach tablet. You can disinfect everything: floor, shoes, objects, packages, shopping. For fruits, vegetables, with a thick envelope only, which you will have to peel anyway, you will need a quarter dilution to the previous one mentioned, (i.e. 1 / 8th bleach tablet in 500cc), and rinse well with water after 20 s. Never apply on fruit without thick skin like strawberries for example. Attention, to respect this well, because risk of poisoning with chlorine. Less risky, you can rinse them with very hot water at around 60-70 degrees. Foods like bread or cakes can be ironed for 120 seconds in an oven. The virus is deactivated in one second at 100 degrees.

Ultraviolet lamps.

Used in the medical field for sterilization, they can destroy the virus. They exist commercially for parts and also for objects.

Small portable lamps and sterilization lamps with UV C with or without Ozone. Dangerous for eyes, it is necessary to wear special protective glasses and do not direct on the skin.

Toilets: a hotbed of contamination.

One researcher had already experimented with tagging an E. coli, seeding a drop in the toilet bowl, and then getting test participants to flush the toilet. The bacteria was immediately found in their throats or noses.

In 1975, the team of Charles P. Gerba et al (Baylor College of Medicine, Department of Virology in Houston) conducted a comprehensive study with different viruses and bacteria. After flushing the toilet, they detected these same viruses or bacteria up to 4 hours later as airborne particles, as well as on the edges of the toilet bowl, on the walls, and even at a certain distance from the toilet bowl. Conclusion: always close the toilet lid before flushing (10).

Another study (11), carried out by Best et al (Leeds, 2012) with the Clostridium difficile bacterium, showed the importance of flushing at least 3 times (even if not so great for the environment); C. difficile was detected on the edges of the toilet bowl 90 minutes after flushing.

Both these studies make it clear how persons contaminated with coronavirus, excreting their virus via the respiratory and digestive tracts can transform toilets and restrooms into a festering hub of contamination since flushing a toilet leads to aerosolization.

In the case of containment, it makes perfect sense for all, contaminated or not, to wear a mask when going to the toilet, particularly if public toilets, and to disinfect them.

At the moment however, this aspect is receiving no attention and its importance is underestimated.

Contamination by the ventilation pipes of the toilets on the upper floor in a building has been described and thermal camera images have made it possible to see the hot air rising to the overlying windows, therefore with potential aerosols. We sometimes smell cigarette smoke or the smells of the apartment below, carried by gases and aerosols, so it can be the same for aerosols carrying odorless viruses.

addition: March 2020, confirmed by another study published in JAMA of March 4, 2020 with the Cover

Shoes: remove them when entering your home and disinfect the floor.

There can be no doubt that heat is a good way to fight against viruses.

Inactivation of viruses by heat

The thermal resistance of the coronavirus has been extensively tested (15, 16, 17, 18) in vitro, on neutral supports. The results are variable: the higher the temperature, the greater the chances of destroying it quickly. It therefore follows that more time is required at lower temperatures. 

Some researchers have reported a reduction in particles of 10 million after 60 minutes at 56°C, whilst other researchers have claimed that viral inactivation is obtained after 6 minutes at 71°C, after 30 minutes at 60°C, or after 15 minutes at 65°C (18).

By studying similar viruses in thermal resistance such as Norovirus (14, 19) in oysters, the virus is no longer detected after 1 minute heating at 67°C.  Another study with contaminated mussels, subjected to temperatures ranging from 50°C and 72°C, shows that the D-value, (i.e., the time after which 90% of the viruses have been inactivated), varied between 5 to 20 minutes.

(addition of recent data from April 2020: The Covid would be destroyed in 4 minutes at 63 °, which corroborates the previous data).

Inhalation of humid hot air at temperatures greater than or equal to 56°C: Proposal for a simple inhalation protocol and Proposal for a resuscitation protocol.

The idea isn't new: at least four studies (6, 7, 8, 9) can be found in the scientific literature available on the Medline database (U.S. National Library of Medicine). All concluded that inhaling heated vapor is entirely ineffective.

However, we would note the following: these studies were all carried out between 42°C and 44°C using an inhalation apparatus of which the face mask had holes and therefore we cannot be sure that this temperature range was maintained. Moreover, the studies did not measure the consequences of varying the waiting time before first applying the inhaler, nor the rhythm of application. At 42°C, on average, no virus is inactivated.

Working from a scientific logic, we wish to propose a protocol to reduce significantly, albeit not completely, the viral load of all viral particles deposited especially in the ENT sphere because coming from an aerosol of 5 microns caused by the expiration of a contaminated person (24). The body has a thermoregulation mechanism whereby inhaled hot air is cooled to around 37°C. However, the inhaled heat creates a temperature above 56-60°C in the nose, throat, trachea and large bronchial tubes. By alternating inhalation between the nose and the mouth, we are sure that the mucous membranes of the ENT sphere and the tracheo-bronchial tract are exposed to this heat. Some smaller but rarer particles will nevertheless go into the alveoli. Respiratory viruses spread from top to bottom, along the respiratory tree, as one would expect.

Then there is the issue of heat tolerance when inhaling. We need to find the best compromise between keeping the temperature as high as possible and yet making it bearable for the person inhaling. In hammams, 50°C is tolerated without any problem. The same goes for saunas, with temperatures as high as 85C°. With an inhaler however, once the temperature reaches about 75°C, users will tend to burn the tip of their nose when inhaling. After carrying out several tests with a thermal probe, varying the waiting times before first applying the inhaler, using standard plastic inhalers with 500cc of water (i.e., large inhalers), we reached the conclusion that, except for young children, this protocol is of potential interest for all users in reducing captured viruses. We posit that this method presents several advantages: easy to implement, entirely safe, and practically free since only heated water is required (note: electric inhalers are not to be used since they only heat water to 45°C).

One should, by contrast, abandon the idea of putting hot water in a bowl with a towel for thermal sealing; the temperature drops too quickly (to under 55°C in less than a minute) and so it is not effective.

(addition of recent data April 2020: Contact time of the virus before penetration approximately 10-12H, preferential penetration of predilection of Covid by the nose, very rich in ACE2 receptor; these data push to make the high temperature preventive inhalation at the end of the day rather )

The protocol for an inhaler

- Use basic adhesive tape to seal off the holes in the plastic inhaler.

- Put boiling water in a 500cc inhaler.

- Wait for 90 seconds, leaving the inhaler with the lid on, but the mouthpiece open.

- After 90 seconds, inhale as slowly as possible so that the heat is applied to the mucous membranes for as long as possible. Then exhale the air away from the mouthpiece as hard and as quickly as possible and re-apply the inhaler as quickly as possible. Users might experience difficulties in the 1.5 to 2.5 minute interval; in that case, the user should inhale for a shorter period if there is a burning sensation at the tip of the nose. Very quickly, users experience no difficulties in achieving slow and deep inhalation. Any difficulties encountered with inhaling can be resolved by simply applying less pressure to the inhaler.

- As we mentioned earlier, it is important to alternate between nose and mouth. Specifically, the user inhales through the nose, disengages from the inhaler mouthpiece, exhales very rapidly, goes back to the inhaler and inhales slowly through the mouth, repeating the cycle for 6 minutes. Thus, the total duration of the protocol, from the beginning, will be 7 minutes and 30 seconds.

Thus, with the suggested protocol as described above, the ENT sphere and the tracheo-bronchial tract will have been exposed for 6 minutes to a temperature of at least 60°C, and this will have the effect of reducing the viral load. Ever better, the viral load may be completely eliminated if the protocol is applied very quickly with respect to the concept of contact.

(addition April 2020: a short protocol with immediate inhalation, steam at around 80 degrees, 5 very slow inhalation through the nose and 5 through the mouth interspersed with ultra-fast exhalation outside. Duration approximately 2 minutes 30 s - Disadvantage: risk of burns of the nose, easily alleviated by a Biafine style cream placed at the end of the nose and small dressing on the end of the nose. These two protocols are under study)



The method is contraindicated for children under the age of five; their mucous membranes are highly sensitive to heat. In the case of children aged between five and eight, we advice caution since the child could spill over the inhaler with the boiling water. In any case, parents should keep a watchful eye on proceedings and hold the inhaler as a precaution. Moreover, if used with children aged five or older, wait 2 minutes 30 seconds before starting and do not exceed 5 minutes of inhalation in total. The method is also contraindicated for people prone to nosebleeds and on anticoagulant medication. We recommend your consult your doctor in these cases.

Except for the above reservations, the protocol is risk-free. There is no need to add anything but water since it is the heat that reduces the viral load. For asthmatics, we recommend, having first consulted with their doctor, that they use their bronchodilator 15 minutes beforehand. While this may cause some nasal congestion and sometimes a slight sore throat, these discomforts will not last and are of no consequence. Just space out the inhalations and shorten them by one to two minutes.


Application of the Protocol

May 2020-A Pre print, preparatory article is in progress, with scientific orientation value, for publication)

Whilst the protocol detailed in the previous paragraphs has not been validated nor randomly studied at this temperature, we are convinced of its salience and potential interest. This is because the protocol is underpinned by incontrovertible scientific facts. The protocol is entirely safe. And we are facing an emergency.  We are of the opinion that it is neither necessary nor reasonable to wait for our analysis to be published in a scientific journal. For two reasons. Firstly, too much time would be required for the article is validated by a reading committee and published, and secondly, such journals tend to prioritize established researchers or department heads.  This is why we agreed, on March 2, 2020, to have our article published on Médiapart, a widely-read online French journal.

It would be desirable for the scientific community to resume studies on preventive and curative inhalation at these temperatures, determine the best combination in terms of duration/temperature/frequency and assess, in confined spaces, the effectiveness of the suggested protocol in curbing the epidemic.  We consider it logical and reasonable to suggest that, combined with all other measures, the generalization of this nose/mouth inhalation protocol to all, for three weeks in a row, would contribute considerably to curbing this pandemic.

It goes without saying that this protocol easily lends itself to all cases of influenza-like illnesses. For example, if a family member is affected, or if you’ve been in contact with a person exhibiting ILI symptoms (fever, cough, blocked or runny nose, sneezing, sore throat, etc.), you and others can immediately have recourse to this protocol, making sure however to do so within no more than 8 hours of being in contact with the (potentially) infected person, repeating the protocol for as long as the person is ill or is showing symptoms.

Whilst it is not the purpose of this article to discuss the optimization of inhalers, there are indeed a certain number of design features and improvements that could be explored.

Proposal of a Resuscitation Protocol for Severe Acute Respiratory Syndrome (SARS)

The proposed protocol should be tested on a small cohort first.  It involves ventilating with hot air at 60 degrees in 3 to 5 sessions, lasting at least 6 minutes, with refrigeration of the rest of the body to control thermal homeostasis. For patients on extracorporeal circulation, it is proposed to heat the blood to 56-60°C in order to decrease the viremia and thus the viral load.  As was found at the time of the Contaminated Blood Scandal, heating units of blood to 56°C for 8 minutes almost completely reduces HIV viremia (although more efficient methods now exist).

No measures should be overlooked.

We would make a final observation concerning hyper-exposed healthcare professionals: a 2004 study (23) by Wang et al (China-Japan Friendship Hospital, Beijing) showed that, during the SARS-CoV epidemic, out of 1127 healthcare professionals assayed, 2.57% had antibodies, but no SARS was found. Under the protocol in place, the nurses and doctors essayed had donned an FFP3 mask well before entering in contact with patients, and had washed their hands frequently. The findings of this study are most reassuring, and clearly show us the way forward: if everyone wore such a mask, the COVID-19 epidemic would be stopped for sure, without slowing down the economy.

I would like:

- to pay homage to my colleague Dr Li Wenliang from Wuhan who sounded the alarm and who died at the age of 34 from this virus;

- to express my solidarity with my colleagues, researchers worldwide who are working hard to find a solution, and state authorities coping on-the-fly as best they can, as well as the Chinese and Japanese authorities. Without the drastic measures taken by the latter, the epidemic would have been even more extensive and dazzling. Many drugs are being tested at the moment.

The proposal made by Professors Colson and Raoult (Marseille, France) to use Nivaquine merits keen interest, especially since a recent Chinese study (Guangdong, February 20, 2020) confirmed the effectiveness of a treatment consisting of 500 milligrams of Nivaquine, twice a day, for 10 days (the prophylaxis for malaria is 100 milligrams per day). Again, it should be noted that stocks of Nivaquine are blocked.

To end on a high note: 99% of people infected by the COVID-19 recover.

Followed by a reminder: People over the age of 60 or with frailties would do especially well to heed these precautionary measures.







1- Wear an FFP3 mask. Everywhere. All the time. Everyone. You’ll get used to it very quickly.  Especially, don a mask when in public transport (trains, subway, taxis, buses, etc.), airports, train stations, or at public events (shows, sports events, etc.).

2- If there is a shortage of masks: A- reuse them by heating them with very hot air from a hair dryer, doing so every 4 hours taking care not to damage the structure of the mask.

(addition after study under the microscope - April 2020: adding a sheet of thick absorbent paper folded in four or a PM2.5 filter under a fabric mask, a surgical mask or any barrier in front of the face considerably improves filtration around 95 % about)

B- At the very least, wear a scarf or a very large 3-ply handkerchief or a thick small towel wrapped tightly over the nose and mouth, also to be dried with very hot air from a hair dryer, every 4 hours, then washed in the evening, while waiting for masks to be delivered.

3-  If no masks are available, stay at least 2 meters from people, and keep elements of furniture as far from each as possible (office tables, chairs, restaurant tables, etc.). Of course, you won’t be able to eat wearing a mask, but you should put it back on immediately at the end of the meal. Waiters and cooks should wear masks.

Restaurant: We could eat with a mask, by lifting the bottom of the mask to bring to the mouth a drink or a bite, without speaking and very quickly. Especially since at that time we do not expire, then put it immediately on the face. The risk would be reduced to spread an aerosol. For restaurants, without drafts, partitioning systems and aerosol suction upwards would allow faster reopening, with precise pedagogy at the entrance and monitoring of the proper wearing of the mask.

4- Require the mask or scarf (with the absorbent sheet folded in four or a PM 2.5 filter) at the entrance and everywhere in all shops and all gatherings, being very strict on this measure. At this price, the economy will not slow down and rallies will be possible. For shows, it is perfectly possible, with absolute rigor over the proper wearing of an effective mask, in cinemas with very tight surveillance, for the theater, more complicated for the actors but possible all the same with mask, for the dancers would require surgical masks (the ffp2 and P3, are difficult on intense efforts); as for the musicians, with the wind instruments and perhaps a little the violinists, no problem for the mask. For wind instruments, a fine felt at the mouth would only slightly affect the sound quality and, on the other hand, would allow the expired air to be filtered. Partitioning with these musicians would be necessary. Sterilization by UV C and OZONE lamps at the end of the show will be very useful.

5- Wash your hands and disinfect them, very frequently. Do not shake hands. Cough or sneeze into a disposable handkerchief, not into the elbow. At worst, bend your head down a lot and cough to the side and a little behind if the person is facing you.

6- Whenever you go to the toilet, proceed as follows: wear a mask, wash your hands, put down the toilet seat (using tissue paper to touch it), flush twice, disinfect the bowl, put enough paper at the bottom of the toilet (on top of the water) before using the toilet, close the toilet seat, flush twice more, do not touch anything or your face, wash your hands again before leaving the toilet.

7- Disinfect smartphone, keys, holders, and other frequently used objects. Disinfect door handles and elevator buttons. Moreover, masks should always be worn inside elevators.

8- In case of shortage of alcohol-based hand sanitizers, it is better to use diluted chlorine (bleach), or even alcohol at 45 degrees, a multitude of disinfectants for toilets, or even Betadine slightly diluted would be better than nothing.  You can even make your own  sanitizer using alcohol at 90°(medical prescription), hydrogen peroxide, glycerine and water solution mixed in the following proportions, for a 500cc solution: 420cc alcohol, 20cc hydrogen peroxide at 3%, 5cc glycerine and 60cc water. Shake well and mix. Then apply using small sprayers commonly found in pharmacies or shops.

9- Inhale according to the protocol. At least once a day at the end of the day. If you can, apply the protocol twice per day (1pm and at bedtime). Space out the inhalation sessions, if you need to.

10- Get into the habit of asking people, while keeping your distance, if they have one or more of the following signs: runny or stuffy nose, sneezing, sore throat, cough, fever, fatigue, headache, fever, muscle aches and pains, either now or over the past few days. Prepare a memo and put it on public display to raise awareness and ensure that you proceed systematically.

11- The Government: A- Increase the production capacity of FFP3 masks for the entire population, including masks made specifically for children. Co-finance the super-fast building of other factories. B- Set up cells to explain these hygiene rules for all.

12- For the medical community: Launch, without further delay, studies on the preventive and therapeutic effectiveness of viral inactivation attained by inhaling very hot air, and on resuscitation aspects pertaining to severe acute respiratory syndromes.

If these measures are properly implemented, the pandemic will begin to really stop within 4 weeks, without slowing down the country's economy.  The virus is transmitted through the air and through toilets. These measures, easy to carry out, are clear and precise and must be implemented now without concession. We are faced with a national and global issue of extreme urgency. Moreover, measures taken now and habits acquired now will stand us in excellent stead to combat other respiratory viruses.


Dr. Pierre-Jacques Raybaud

General Practitioner - Post-Graduate Diploma in General Immunology


Translator: Samuel Young




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