1.5 meters distance only works if the air is moist enough.
Why are there more corona infections after the summer? The government would have us believe that it's only because we don't adhere to the measures enough, but Edsard Ravelli researched a more important factor; humidity and UV light. 1.5 meters only works if the air is moist enough. Humidity ensures that virus particles within 1.5 meters fall down and do not float and still cause infection in indoor spaces.
1. What does Ravelli's research involve?
2. How does infection by a coronavirus work?
3. What else can we do to reduce corona infections?
1) What does the Ravelli investigation entail?
Edsard Ravelli has, in his own words, demonstrated a causal relationship between air humidity and the number of coronavirus infections (e.g., there would be more infections at low air humidity). He wrote about his findings to Mark Rutte, Hugo de Jonge and His Royal Highness Willem Alexander, among others. Professor Jeffrey Shaman wrote a paper in 2009 about airborne viruses and concluded that the lower the humidity, the higher the risk of respiratory infections.
Ravelli replicated this conclusion with Dutch figures
He collected data from:
1. RIVM with the number of positives tested, number of hospitalizations and mortality rates by municipality;
2. KNMI for data from 37 monitoring stations across the Netherlands over the past 20 years and access to current weather data from those stations. Here, humidity, wind direction and solar radiation (UV light) proved to be of great importance in predicting the spread of influenza viruses. (e.g., influenza and SARS)
3. CBS for data related to population movement behavior
4. NIVEL, a public knowledge organization supervised by RIVM, for data on influenza per municipality per week over the past five years.
He had two universities analyze this data to see if there was a causal relationship and a causal relationship between the data, without them knowing what kind of data it was.
All analyses showed that a causal relationship could be established between air humidity and virus infections spread by droplets in the air.
By modelling this, he managed to predict the number of coronas infections (based on hospital admissions and mortality) with 95% accuracy, according to Ravelli.
2 How does infection by a coronavirus work?
First of all, what is the difference between a virus and a bacterium?
A bacterium is a living organism and grows by dividing itself. A virus is not a living organism and is made up of RNA or DNA. A virus actually works just like a computer virus: it enters your body like a virus enters your computer's operating system. There it gives commands to change things. If a virus enters your mucous membrane through your nose/throat, you can compare this to a virus going through the firewall. Sometimes the firewall can stop the virus like a snotty nose or throat also sometimes manages to stop a virus. The deeper the virus penetrates your mucous membranes, and then gets into your vulnerable lungs, the more damage it can do because the firewall is no longer as strong here.
Once the virus is through the mucosa, it can attach itself to the cells like a usb stick, with its spikes. You can think of this spike, of protein as a kind of garden hose that attaches itself to the cells. From that moment on the virus can give the cells a command. For example, to start dividing. From the moment the cells are infected by the virus, they will start giving instructions to other cells. This is called replication. And so the virus spreads in your body and more and more cells become infected.
What is the difference between influenza and corona.
Both influenza (which causes flu) and SARS-CoV-2 (which causes COVID-19 ) are envelope viruses. That is, they have a kind of spacesuit on and inside is the RNA and the DNA. In coronavirus there is RNA and in a flu virus there is DNA.
A flu virus has an incubation period of 1 to 3 days. Within three days you get symptoms.
The coronavirus has an incubation period of 5 to 6 days, this is because it is a new virus and our body does not recognize it yet. Because of this, it takes longer for the body to show a reaction. That's why people stay around longer as with a flu virus, without knowing it; however, 2 to 3 days before you have symptoms you are already contagious.
Most are sick for 2 to 3 weeks, after which it can still go wrong and you end up in the hospital. In the worst case, people die and this is on average 5 weeks after the first symptoms of illness.
So there are 3 transmission routes:
- Direct contact: that's why you shouldn't shake hands;
- Through big drops: that's why we have to keep 1,5 meters distance;
- Via small droplets (aerosols): this is why we need to humidify and ventilate the air.
Humidity is needed for 1.5 meters to be safe.
Air can only hold a limited amount of moisture, with the amount of moisture depending on the temperature.
We usually only see that moisture (water vapor) is contained when it cools down and the windows fog up. Colder air can contain less water vapor than warmer air.
Our lungs, throat and nose are moist, and the virus droplets that are there if one is infected contain a relatively large amount of water. As a result, it is relatively large and heavy and therefore falls to the ground within 1.5 meters. Therefore, we must keep the 1.5 meters distance to avoid contamination.
At the moment when the air is very dry, a large virus droplet, which can contain as many as 100,000 water droplets, can snap. Then it becomes very light and starts to float.
When the moisture outside is as moist as your breath, then the water has nowhere to go and the big drop falls to the ground. When it is dry, then the water droplet bursts and enters the air, where it can spread. Ventilating is then not even sufficient anymore. So it is more important to keep the humidity high so that there are no or less infected small virus particles in the air.
3 What else can we do to reduce corona infections?
Because from October onwards the sunlight is insufficient and the humidity too low to positively influence the spread of the virus, it is important to place humidifiers, preferably with UV lamps, in homes, schools, public buildings, health care institutions (and soon also in the hospitality industry when it is allowed to open again).
Also, the heating is on more and more from which the air becomes dry and it is necessary that you humidify even more. The smaller your space, the less you need to humidify. The larger the room, the larger the humidifier needs to be.
Opening a window often does not help enough to increase the humidity in the house: the outside air in winter can actually be colder and therefore drier than the air inside.are and therefore drier than the air inside. To increase humidity in the house, aids are often used. For example, a container with water or a wet tea towel near the heater. However, these tools do not help enough to reach the optimal humidity of about 50%.
A safe margin for relative humidity depends on the (room) temperature.
For example, at 21 degrees the relative humidity should be 50%,
At 18 degrees, the humidity should be 65%.
The more humid the air is, the more humid your mucous membrane is: this also makes your firewall work better to stop the virus.
Humidification helps not only for the SARS-Cov-2 virus that causes COVID-19, but also for the common flu.
The Covid-19 tests can be found via this link
Measuring infections at your company location:click here