We have all had to deal with the corona crisis in one way or another. Stress, sadness, fear, restrictions, an overloaded health care system, loss of income, bankruptcies, etc …mOur entire society has been affected. Especially the ones most vulnerable, such as the elderly, are still having a hard time. And there are also many unanswered questions such as: How long will this crisis last? What does our future look like? How effective are the measures? Independent scientific research is more important than ever. Read on and / or watch this very important video.
Please Donate Research into Humidity

The effects of Humidity on the spread

We want to reiterate that we are proponents of the WHO guidelines of ‘Social Distancing’ and ‘Hygiene’. Undisputed scientific research has proven that SARS-CoV-2, causing the illness COVID-19, spreads through 2 mechanisms, namely;

Direct contact Close contact ?
Until recently most people were convinced that respiratory viruses only spread through:

1. Direct contact (direct person-to-person contact such as handshaking)

2. Expiratory droplets (sneezing/coughing droplets, travelling a few feet)

This is the reason why many governments have enacted Hygiëne en Social Distancing‘ guidelines. Measures such as: lock-downs, curfews, closure of shops, schools and restaurants all have the same goal; avoiding contact – and thus infection – between people. Many scientists and researchers, including us, have long suspected that there is a third route that the virus also travels. A ‘floating’ route … responsible for at least 50% of the infections.

Since march 2020 my fellow researchers and I have been investigating a possible relationship between respiratory viruses: Influenza (‘the flue’) and SARS-CoV-2 (COVID-19) en Specific Humidity (q). For our research we used detailed weather-, influenza, COVID-19, Hospitilization, mortality and other statistical data, granted to us by Dutch authorities; RIVM (Dutch CDC), KNMI (Dutch National Weather Service) and the Central Bureau of Statistics (CBS).

New Modeling Techniques

Earlier research has proven that microscopic droplets, that can remain afloat, do exist in Influenza viruses. But academics, for good reason, were hesitant to compare influenza to COVID-19. Until recently. New research, done by various universities, now shows that expiratory droplets, containing a virus, include water, salts and organic material. We played an important role is these discoveries. If, upon expiration, some of the water content evaporates, the microscopic droplet becomes small and light enough to stay suspended in the air. This is how microscopic droplets are created. Microscopic droplet concentration in the air builds up (called ‘Viral load’), increasing the risk of infection, particularly if the air is stagnant as in many indoor environments in public places with insufficient and inefficient ventilation.

Using the latest (Spatial and Spatio-Temporal) modeling techniques, we analyzed the weather data, infections, hospital admissions and mortality rates between all 355 municipalities in the Netherlands on a daily basis. For a period of five months. Specific Humidity (q) explained a significant part of the case differences between the different municipalities. We were not only able to make a direct connection between Specific Humidity (q) and the spread of these respiratory viruses. We were also able to gain insight into the actual effect of different Specific Humidity (q) levels. That effect is significant. When the Specific Humidity (q) decreases, we see a clear rise in COVID-19 cases. When the Specific Humidity (q) increases, we see a clear and calculable decrease. Using our modeling techniques, we were able to make a number of predictions about the spread of the coronavirus. All those predictions have come true. With an error margin of only one week. Which in academic terms is monumental. And that gives confidence in the quality of our research and the modell we were able to develop..

We also modelled with Influenza. Explanation of the graphs below. The blue upright bars are the number of Influenza infections per week, as measured for Nivel. The up and down (from left to right) brown line is the specific humidity, measured by the KNMI (Dutch National Weather Service). The green bar is a specific humidity of 8 g / kg or more (that is a relative humidity of 50% or more at 21 Celsius). The orange bar is a specific humidity of between 7 g / kg and 8 g / kg (that is a relative humidity of + – 45% or more at 21 Celsius) and The red bar is a specific humidity of 6 g / kg or less (that is, a relative humidity of 40% or less at 21 Celsius). But does this also apply to SARS-CoV-2, the corona virus?

How Humidity plays a role

Because of our research – “Environmental risk factors of airborne viral transmission: Humidity, Influenza and SARS-CoV-2 in the Netherlands” – we conclude that Specific Humidity (q) influences both Influenza and SARS-CoV-2:
  1. The “expiratory droplet”, also known as the respiratory droplet, evaporates making it lighter and able to float for a longer period of time. This micro droplet then changes, as it is often referred to in the media, into an ‘Aerosol’. The lower the Specific Humidity (q), the lighter the drop becomes and the longer it can float. The more of these ‘Aerosols’ we breathe in, the greater the chance of becoming infected.
  2. A low Specific Humidity (q) also causes our mucous membranes (‘Mucosa’), our natural barrier against viruses, to dry out. Think of your mucous membranes as a “bunker” made of slime. The bigger and stronger the “bunker”, the better the protection. Slime, as you know, contains water. The more water, the more slime, the thicker and stronger our “bunker”. That is also why we are more susceptible to respiratory viruses in winter. Due to the low humidity, our “bunkers” are less large and strong. Increasing the humidity ensures that our “bunkers” remain strong.
  3. Surface inactivation. An enveloped virus loses its infectivity dramatically (up to four orders of magnitude) due to aeration. The hypothesis is that enveloped viruses are likely to accumulate at the surface of droplets, where “unbalanced forces” acting on the virions (ie. the viral particle itself) may be strong enough to produce inactivation through irreversible unfolding and rearrangement of molecules. Basically the ‘Balloon’ bursts. And the virus can’t live outside of its balloon.
  4. The salts. The salts in the respiratory droplets, when the aerosol is formed, actually create a shield that protects the virus while airborne. When the aerosol hits your mucous membrane (ie. the tissue in your lungs for example, the salt-shield actually allows the virus to penetrate deeper. When it hits its destination, the slime actually hydrates the salt-shield, dissolving the shield and allowing the virus to infect your tissue very efficiently. The opposite is also true; High humidity avoids the salt-shield getting formed.

Perhaps good to know:
We have all become used to the term “Relative Humidity”. This is expressed as a percentage (%). What many people don’t know is that Relative Humidity (RH) is relative to the temperature. In other words; a RH of 70% at 8 degrees Celsius is drier than a RH of 40% at 20 degrees Celsius. Specific Humidity (q) actually measures how much water vapor is present in the room, regardless of the temperature.

A Specific Humidity of 6g/Kg is equal to:
– Relative Humidity of 40% at 21 degrees Celsius or 70 degrees Fahrenheit
– Relative Humidity of 45% bij 17 degrees Celsius or 63 degrees Fahrenheit

Peer-Reviewed Research

Our research has been published in a scientific journal specializing in Epidemiology (scientific study of the occurrence and spread of diseases within and between populations), called Spatial and Spatio-Temporal Epidemiology, after undergoing a ‘Peer-Review’.

Perhaps good to know:
The peer review process subjects an author’s scientific work, research or ideas to the scrutiny of others who are experts in the same field (peers) and is considered necessary to ensure academic scientific quality. Policy makers therefore often rely solely on peer-reviewed papers.

There are three routes, not two

Direct contact Close contact Through the Air
Our conclusions, including caveats*, have far-reaching implications for possible measures against COVID-19. For example, the spread of respiratory viruses in indoor and communal areas is very different from outdoors and is largely dependent on the weather (humidity is one of those factors). This means that there are 3 routes that the virus can travel; “Direct contact”, “Close contact” and – under certain circumstances – “Through the air”. In this video we explain all three routes.
Bron: Edsard Ravelli op YouTube

Measures, factors and weather

A peer review process, especially if the conclusions can have far-reaching consequences, is an excellent way to conduct independent and objective research. Then commercial and / or political interests do not play a role. It is purely about science.
This is how we were put to the test during the review process. Not only were our models critically examined. One of the challenges we were presented with was, rightly, whether we sufficiently took into account the public health interventions (ie. measures), such as lock-downs, curfews and masks. And whether we correctly accounted for the closure of schools, bars, restaurants, nightclubs and gyms. In short: we were pushed to proof that we had sufficiently taken into account “the human factor”. We see a similar debate all over
the world …
After this process was completed, we, the fellow scientists and the journal concluded that we had sufficiently taken into account “the human factor”. This has led to a firm conclusion, especially for academic standards.

Policies that lead to an increase in household specific humidity to over 6g/Kg will help reduce the spread of respiratory viruses such as influenza and SARSCoV-2

The monumental consequences of our research

I cannot stress enough how important this discovery is. Partly because of this research:
    1. It has now been established that there is a third route, infections by ‘Aerosols’
    2. All future epidemiological models will take weather influences, such as Humidity, into account
    3. By taking the weather data into account, the forecasting of viral transmissions will become more accurate
    4. More effective and timely measures can be enacted
    5. We have more ways to prevent the spread of viruses. Humidification being one of them

But we are not there yet…
Using our newest models, whereby we integrate weather data, we can conduct much more important and independent research. For example: We’ll be able to help governments more accurately map the effectiveness of all measures and other factors, independently. Without being influenced by commercial and / or political interests.
But we need your help with that.


Our followup research. Modelling and experiments

I would like, together with my fellow scientists and researchers, to remove as much uncertainty as possible with regard to the consequences of: “Measures”, “Weather influences” and “other factors”. Our goal is to investigate all factors that influence the spread of SARS-CoV-2. The best way we can do this is to conduct research, publish our findings and have them peer reviewed.
We will conduct our research in two ways:

(i) Modelling, like with did with Humidity

(ii) Experiments, where we research additional preventative solutions



We have designed a more detailed, quantitative study with data from both the Netherlands (many and strict measures) and Sweden (few measures). We see that both the Netherlands and Sweden have had a similar infection pattern. We expect this to be due to a similar weather pattern. By analyzing the data from both countries, we can more accurately determine whether and what impact government health interventions and other factors have had on the spread and effects of the coronavirus. We are going to take into account all kinds of other data sets, such as: Population makeup, Population density, Work situations, Travel behavior, Holidays, Age, BMI, Prevalence, Exposure, Group immunity, Virus Mutations, etc …

This research will help determine independently and objectively quantify the impact of government policies, such as lockdown, curfews, closures and other guidelines.

We believe in transparency. That is why we will process our findings and models in a new version of We expect to be able to make very accurate predictions as a result. Among other things, about the effects of the weather, the measures and other factors. We expect that this can lead to a better and more regional policies, across the world. We will use The Netherlands and Sweden as the worlds’ modelling petri dish.


We will also be conducting new types of experiments with the help of test setups. This allows us to investigate the effects of various other possible solutions. Such as: Humidification, Air Purification, Ventilation, and UV Lighting. Much has been written about it in the scientific literature. But as the saying goes:

“The proof of the pudding is in the eating”

By doing these two studies, we hope to answer the following questions definitively:
    • What impact do all weather factors, if any, have on the Coronavirus?
    • What impact does each measure, if any, have on the coronavirus?
    • What impact does our behavior, if any, have on the Coronavirus?
    • What impact does (group) immunity, if any, have on the Coronavirus?
    • What lessons can we learn from the above answers?

Help us stay independent

Whose bread one eats his word one speaks.

Independent scientific research, especially during this corona crisis, is extremely important. But it is also very expensive. Hiring scientists, researchers, designers, programmers and fabricators is not cheap. And that is in addition to all kinds of other (running) costs. Such as leasing servers, computing power (for our models), building test setups, etc.

You can support our research and help makes things better for everyone. You can support us by:

    1. Becoming a corporate sponsor
    2. Donating to our cause

This way we can continue our incredibly important work.
Will you help?

Thank you in advance,

Edsard Ravelli

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